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Assertion-Reason MCQs for Sub-Topics of Topic 2: Algebra
Content On This Page
Fundamentals of Algebra: Variables, Expressions, and Basic Concepts Operations on Algebraic Expressions Polynomials: Definition, Types, and Properties
Polynomial Theorems and Division Algebraic Identities Factorisation of Algebraic Expressions and Polynomials
Linear Equations in One Variable Linear Equations in Two Variables Pair of Linear Equations in Two Variables: Systems and Solutions
Quadratic Equations: Introduction and Solving Methods Complex Numbers: Introduction and Algebra Complex Numbers: Representation and Properties
Quadratic Equations with Complex Roots Linear Inequalities Sequences and Series
Principle of Mathematical Induction Counting Principles: Factorial, Permutations, and Combinations Binomial Theorem
Matrices: Introduction, Types, and Basic Operations Matrices: Properties and Advanced Operations Determinants and Adjoint
Inverse of a Matrix and Systems of Equations Applications of Algebraic Equations in Word Problems


Assertion-Reason MCQs for Sub-Topics of Topic 2: Algebra



Fundamentals of Algebra: Variables, Expressions, and Basic Concepts

Question 1. Assertion (A): In the algebraic expression $5x^2 - 3x + 7$, the term $7$ is a constant.

Reason (R): A constant term in an algebraic expression has a fixed numerical value and does not contain any variables.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): In the term $-4ab$, the coefficient of $ab$ is $-4$.

Reason (R): The coefficient of a term is the numerical factor that multiplies the variable part.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): The expression $p/q$ is an algebraic expression.

Reason (R): An algebraic expression is formed by combining variables and constants using the operations of addition, subtraction, multiplication, and division.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): The value of the expression $2x + 1$ when $x=5$ is $11$.

Reason (R): To find the value of an expression for a given value of the variable, substitute the value into the expression and perform the calculations.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): $3a^2b$ and $5ab^2$ are like terms.

Reason (R): Like terms have the same variables raised to the same corresponding powers.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Operations on Algebraic Expressions

Question 1. Assertion (A): The sum of $4x - y$ and $x + 2y$ is $5x + y$.

Reason (R): When adding algebraic expressions, we combine the coefficients of like terms.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): The product of $(x+1)$ and $(x-1)$ is $x^2 - 1$.

Reason (R): The difference of squares identity is $(a+b)(a-b) = a^2 - b^2$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): The result of dividing $12a^3b^2$ by $4ab$ is $3a^2b$.

Reason (R): When dividing monomials, we divide the coefficients and subtract the exponents of corresponding variables.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): Subtraction of algebraic expressions is commutative.

Reason (R): $A - B = B - A$ for any two algebraic expressions A and B.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): To multiply a polynomial by a monomial, we multiply each term of the polynomial by the monomial.

Reason (R): The distributive property of multiplication over addition (and subtraction) applies to algebraic expressions.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Polynomials: Definition, Types, and Properties

Question 1. Assertion (A): The expression $\sqrt{x} + 5$ is not a polynomial.

Reason (R): The powers of the variable in a polynomial must be non-negative integers.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): The degree of the polynomial $3x^5 - 7x^2 + 10$ is 5.

Reason (R): The degree of a polynomial is the highest power of the variable in the polynomial.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): A polynomial with exactly two terms is called a binomial.

Reason (R): 'Bi' means two, indicating two terms in the polynomial.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): If $P(2) = 0$ for a polynomial $P(x)$, then $x=2$ is a zero of the polynomial.

Reason (R): A zero of a polynomial $P(x)$ is a value of $x$ for which $P(x) = 0$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): The graph of a quadratic polynomial $y = ax^2+bx+c$ with $a \neq 0$ is a straight line.

Reason (R): The graph of a quadratic polynomial is a parabola.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Polynomial Theorems and Division

Question 1. Assertion (A): When the polynomial $P(x)$ is divided by $(x-a)$, the remainder is equal to $P(a)$.

Reason (R): This statement is known as the Remainder Theorem.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): If $P(a) = 0$ for a polynomial $P(x)$, then $(x-a)$ is a factor of $P(x)$.

Reason (R): This statement is known as the Factor Theorem.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): When $x^2 - 5x + 6$ is divided by $(x-2)$, the remainder is 0.

Reason (R): By the Remainder Theorem, the remainder is $P(2) = 2^2 - 5(2) + 6 = 4 - 10 + 6 = 0$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): $(x+1)$ is a factor of $x^3 + 1$.

Reason (R): By the Factor Theorem, if $(x+1)$ is a factor, then $P(-1) = 0$. $P(-1) = (-1)^3 + 1 = -1 + 1 = 0$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): In the Division Algorithm $P(x) = Q(x) D(x) + R(x)$, the degree of the remainder $R(x)$ is always strictly less than the degree of the divisor $D(x)$.

Reason (R): If the degree of $R(x)$ were greater than or equal to the degree of $D(x)$, the division process could continue.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Algebraic Identities

Question 1. Assertion (A): $(a+b)^2 = a^2 + b^2 + 2ab$ is an algebraic identity.

Reason (R): An algebraic identity is an equality that is true for all values of the variables involved.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): The expression $4x^2 - 9y^2$ can be factorised using the identity $a^2 - b^2 = (a-b)(a+b)$.

Reason (R): $4x^2 = (2x)^2$ and $9y^2 = (3y)^2$, so the expression is in the form of a difference of squares.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): The value of $55^2 - 45^2$ is 1000.

Reason (R): Using the identity $a^2 - b^2 = (a-b)(a+b)$, $55^2 - 45^2 = (55-45)(55+45) = 10 \times 100 = 1000$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): $(x-y)^3 = x^3 - y^3 - 3xy(x-y)$.

Reason (R): The identity for $(a-b)^3$ is $a^3 - b^3 - 3a^2b + 3ab^2$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): If $a+b+c=0$, then $a^3+b^3+c^3 = 3abc$.

Reason (R): The identity $a^3+b^3+c^3 - 3abc = (a+b+c)(a^2+b^2+c^2-ab-bc-ca)$ is true for all values of $a, b, c$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Factorisation of Algebraic Expressions and Polynomials

Question 1. Assertion (A): The expression $5x^2 - 10xy$ can be factorised as $5x(x - 2y)$.

Reason (R): Factorisation by taking out a common factor involves identifying the greatest common factor of the terms and writing the expression as a product.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): The expression $ab + ac + bd + cd$ can be factorised by grouping as $(a+d)(b+c)$.

Reason (R): Factorisation by grouping involves arranging terms and factoring common factors from groups to get a common binomial factor.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): The polynomial $x^2 - 7x + 12$ can be factorised by splitting the middle term into $-3x$ and $-4x$.

Reason (R): We look for two numbers whose product is the constant term (12) and whose sum is the coefficient of the middle term (-7).

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): The polynomial $x^3 - 8$ can be factorised as $(x-2)(x^2+4x+4)$.

Reason (R): The identity for the difference of cubes is $a^3 - b^3 = (a-b)(a^2+ab+b^2)$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): If $(x-a)$ is a factor of a polynomial $P(x)$, then $x=a$ is a root of the equation $P(x)=0$.

Reason (R): A root of an equation is a value of the variable that satisfies the equation.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Linear Equations in One Variable

Question 1. Assertion (A): The equation $5x - 1 = 9$ is a linear equation in one variable.

Reason (R): A linear equation in one variable can be written in the form $ax+b=0$, where $a$ and $b$ are constants and $a \neq 0$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): The solution of the equation $2x+3 = 7$ is $x=2$.

Reason (R): Substituting $x=2$ into the equation gives $2(2)+3 = 4+3 = 7$, which is a true statement.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): Using transposition, $3x = 10 - 4$ is obtained from $3x + 4 = 10$.

Reason (R): Transposing a term from one side of the equation to the other requires changing its sign.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): Multiplying both sides of the equation $\frac{x}{2} = 5$ by 2 gives $x=10$, and the solution remains the same.

Reason (R): Performing the same non-zero arithmetic operation on both sides of a linear equation maintains the equality and the solution.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): A word problem involving finding a single unknown quantity often leads to a linear equation in one variable.

Reason (R): Variables in algebra are used to represent unknown quantities.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Linear Equations in Two Variables

Question 1. Assertion (A): $x + y = 7$ is a linear equation in two variables.

Reason (R): A linear equation in two variables can be written in the form $Ax + By + C = 0$, where $A$ and $B$ are not both zero.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): The equation $x = 5$ represents a straight line parallel to the y-axis.

Reason (R): In the equation $x=k$, the x-coordinate of every point on the line is $k$, while the y-coordinate can be any real number, resulting in a vertical line.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): A linear equation in two variables has infinitely many solutions.

Reason (R): The graph of a linear equation in two variables is a straight line, and every point on the line represents a solution.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): The point $(2, 3)$ is a solution to the equation $x + y = 5$.

Reason (R): Substituting $x=2$ and $y=3$ into the equation gives $2+3=5$, which is a true statement.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): The equation $y = 0$ represents the x-axis.

Reason (R): On the x-axis, the y-coordinate of every point is zero.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Pair of Linear Equations in Two Variables: Systems and Solutions

Question 1. Assertion (A): A system of two linear equations in two variables can have a unique solution, no solution, or infinitely many solutions.

Reason (R): Geometrically, two lines in a plane can intersect at one point, be parallel and distinct, or be coincident.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): A consistent system of linear equations has at least one solution.

Reason (R): If the lines represented by the equations are intersecting or coincident, the system is consistent.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): The system $\begin{cases} 2x + 3y = 5 \\ 4x + 6y = 10 \end{cases}$ has infinitely many solutions.

Reason (R): The ratio of coefficients $\frac{a_1}{a_2} = \frac{b_1}{b_2} = \frac{c_1}{c_2}$ for this system ($2/4 = 3/6 = 5/10 = 1/2$).

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): The system $\begin{cases} x + y = 1 \\ x + y = 2 \end{cases}$ is inconsistent.

Reason (R): Parallel lines represent an inconsistent system.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): The graphical method involves finding the intersection point(s) of the lines.

Reason (R): A solution to a system of equations is a point that satisfies all equations in the system.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Quadratic Equations: Introduction and Solving Methods

Question 1. Assertion (A): The equation $x^2 - 5x + 6 = 0$ is a quadratic equation.

Reason (R): A quadratic equation is a polynomial equation of degree 2.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): The sum of the roots of $2x^2 - 8x + 6 = 0$ is 4.

Reason (R): For a quadratic equation $ax^2+bx+c=0$, the sum of the roots is $-b/a$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): The roots of $x^2 - 9 = 0$ are $x=3$ and $x=-3$.

Reason (R): The equation can be factored as $(x-3)(x+3) = 0$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): The discriminant of $x^2 + x + 1 = 0$ is $-3$.

Reason (R): The discriminant $D = b^2 - 4ac$ for $ax^2+bx+c=0$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): If the discriminant of a quadratic equation with real coefficients is negative, the roots are real and distinct.

Reason (R): A negative discriminant means the roots are non-real (complex).

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Complex Numbers: Introduction and Algebra

Question 1. Assertion (A): $i^4 = 1$.

Reason (R): $i^2 = -1$, so $i^4 = (i^2)^2 = (-1)^2 = 1$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): The sum of $(3+2i)$ and $(1-4i)$ is $4-2i$.

Reason (R): Complex numbers are added by summing their real parts and summing their imaginary parts separately.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): The product of $i$ and $-i$ is 1.

Reason (R): $i \times (-i) = -i^2 = -(-1) = 1$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): The reciprocal of $i$ is $-i$.

Reason (R): The reciprocal of a complex number $z$ is $1/z$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): The real part of the complex number $5i$ is 5.

Reason (R): A purely imaginary number has a real part equal to zero.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Complex Numbers: Representation and Properties

Question 1. Assertion (A): The complex number $2 - 3i$ is represented by the point $(2, -3)$ in the Argand plane.

Reason (R): In the Argand plane, the real part of $a+bi$ is the x-coordinate and the imaginary part is the y-coordinate.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): The modulus of the complex number $-1 - i$ is $\sqrt{2}$.

Reason (R): The modulus $|a+bi| = \sqrt{a^2+b^2}$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): The conjugate of the complex number $5+2i$ is $5-2i$.

Reason (R): The conjugate of $a+bi$ is obtained by changing the sign of the real part.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): If $z$ is a complex number such that $z = -\bar{z}$, then $z$ must be purely imaginary.

Reason (R): If $z=a+bi$, then $-\bar{z} = -(a-bi) = -a+bi$. If $a+bi = -a+bi$, then $a=-a$, which means $2a=0$, so $a=0$. Thus $z=bi$, which is purely imaginary.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): The polar form $r(\cos \theta + i \sin \theta)$ of a complex number is unique.

Reason (R): The argument $\theta$ is unique up to a multiple of $2\pi$, but the principal argument in $(-\pi, \pi]$ is unique.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Quadratic Equations with Complex Roots

Question 1. Assertion (A): The quadratic equation $x^2 + x + 1 = 0$ has complex roots.

Reason (R): The discriminant of the equation is $D = 1^2 - 4(1)(1) = -3$, which is negative.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): If a quadratic equation with real coefficients has $2+i$ as one root, then $2-i$ must be the other root.

Reason (R): Complex roots of a quadratic equation with real coefficients always occur in conjugate pairs.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): The roots of the equation $x^2 - 4x + 8 = 0$ are $2 \pm 2i$.

Reason (R): The quadratic formula for the roots of $ax^2+bx+c=0$ is $x = \frac{-b \pm \sqrt{b^2-4ac}}{2a}$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): The quadratic equation with roots $3i$ and $-3i$ is $x^2 + 9 = 0$.

Reason (R): The sum of roots is $0$ and the product of roots is $9$, leading to the equation $x^2 - (sum)x + (product) = 0$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): The equation $x^2 + kx + k = 0$ has complex roots if $0 < k < 4$.

Reason (R): The roots are complex if the discriminant $b^2 - 4ac < 0$. For this equation, $k^2 - 4k < 0 \implies k(k-4) < 0$, which is true when $0 < k < 4$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Linear Inequalities

Question 1. Assertion (A): $3x + 5y \ge 10$ is a linear inequality in two variables.

Reason (R): It involves linear expressions and an inequality sign.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): When solving $-4x > 8$, we divide by $-4$ and change the inequality sign to get $x < -2$.

Reason (R): Dividing an inequality by a negative number reverses the direction of the inequality sign.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): The solution set of $x \ge 2$ on a number line includes the point $x=2$.

Reason (R): The symbol '$\ge$' means 'greater than or equal to'.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): The graph of $y > 1$ in the coordinate plane is the region above the line $y=1$, excluding the line itself.

Reason (R): The '>' symbol indicates that the boundary line is not included in the solution set.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): The feasible region for a system of linear inequalities in two variables is the area where all inequalities are satisfied simultaneously.

Reason (R): The feasible region is the intersection of the half-planes represented by each linear inequality.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Sequences and Series

Question 1. Assertion (A): The sequence $5, 10, 15, 20, \dots$ is an Arithmetic Progression (AP).

Reason (R): In an AP, the difference between any term and its preceding term is constant.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): The sequence $3, 9, 27, 81, \dots$ is a Geometric Progression (GP).

Reason (R): In a GP, the ratio of any term to its preceding term is constant.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): The $n$-th term of the AP $2, 5, 8, \dots$ is $3n-1$.

Reason (R): The formula for the $n$-th term of an AP is $a_n = a + (n-1)d$, where $a$ is the first term and $d$ is the common difference.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): For any two distinct positive numbers, their Arithmetic Mean (AM) is strictly greater than their Geometric Mean (GM).

Reason (R): The relationship between AM and GM is $AM \ge GM$, and equality holds only when the two numbers are equal.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): The sum of the first $n$ natural numbers is given by the formula $\frac{n(n+1)}{2}$.

Reason (R): The sequence of natural numbers $1, 2, 3, \dots$ is an AP with first term 1 and common difference 1.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Principle of Mathematical Induction

Question 1. Assertion (A): The Principle of Mathematical Induction is a method used to prove statements for all positive integers.

Reason (R): The principle consists of proving a base case and an inductive step that shows the property holds for $k+1$ if it holds for $k$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): In proving $P(n): 1+2+\dots+n = \frac{n(n+1)}{2}$ for $n \ge 1$, the base case is $P(1)$.

Reason (R): The statement needs to be proven for the smallest positive integer, which is 1.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): If we successfully prove the base case $P(n_0)$ and the inductive step $P(k) \implies P(k+1)$ for all $k \ge n_0$, then we have proven $P(n)$ for all integers $n \ge n_0$.

Reason (R): The Principle of Mathematical Induction guarantees that if a property holds for a starting value and propagates, it holds for all subsequent integers.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): To prove $P(n): n^2 > 2n$ for $n \ge 3$, the base case is $P(3)$.

Reason (R): The statement is specified to be true for integers greater than or equal to 3, so 3 is the smallest value for which the statement is claimed to be true.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): Strong induction is a more powerful method than standard induction.

Reason (R): In strong induction, the inductive hypothesis assumes $P(k)$ is true, while in standard induction, it assumes $P(j)$ is true for all $n_0 \le j \le k$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Counting Principles: Factorial, Permutations, and Combinations

Question 1. Assertion (A): The number of ways to arrange 3 distinct objects is $3! = 6$.

Reason (R): $n!$ represents the number of permutations of $n$ distinct objects.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): The number of ways to choose a committee of 2 from 5 people is $\text{C}(5, 2) = 10$.

Reason (R): A committee selection is a combination problem because the order of selection does not matter.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): $\text{P}(n, r) = \text{C}(n, r) \times r!$.

Reason (R): A permutation is a combination followed by an arrangement (of the selected items).

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): $\text{C}(10, 3) = \text{C}(10, 7)$.

Reason (R): The property $\text{C}(n, r) = \text{C}(n, n-r)$ states that choosing $r$ items from $n$ is the same as choosing $n-r$ items to leave behind.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): The number of distinct permutations of the letters in the word 'INDIA' is 60.

Reason (R): The formula for permutations with repeated letters is $\frac{n!}{p_1! p_2! \dots p_k!}$. In 'INDIA', there are 5 letters with 'I' repeated twice, so the number of permutations is $\frac{5!}{2!} = 60$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Binomial Theorem

Question 1. Assertion (A): The expansion of $(x+y)^n$ for a positive integer $n$ has $n+1$ terms.

Reason (R): The terms in the expansion correspond to the values of $r$ from 0 to $n$ in the general term $\text{C}(n, r) x^{n-r} y^r$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): The 4th term in the expansion of $(a+b)^6$ is $\text{C}(6, 3) a^3 b^3$.

Reason (R): The general term is $T_{r+1} = \text{C}(n, r) a^{n-r} b^r$. For the 4th term, $r+1=4$, so $r=3$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): The sum of the coefficients in the expansion of $(2x - 3y)^5$ is $-1$.

Reason (R): The sum of coefficients in $(a+b)^n$ is $2^n$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): The middle term in the expansion of $(x+y)^{10}$ is the 5th term.

Reason (R): If the index $n$ is even, the middle term is the $(n/2 + 1)$-th term.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): The coefficient of the term independent of $x$ in the expansion of $(x + 1/x)^4$ is 6.

Reason (R): The general term is $\text{C}(4, r) x^{4-r} (1/x)^r = \text{C}(4, r) x^{4-2r}$. The term independent of $x$ occurs when $4-2r=0$, so $r=2$. The coefficient is $\text{C}(4, 2) = 6$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Matrices: Introduction, Types, and Basic Operations

Question 1. Assertion (A): Two matrices can be added only if they have the same order.

Reason (R): Matrix addition is performed by adding corresponding elements, which requires the matrices to have the same dimensions.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): Matrix multiplication is commutative.

Reason (R): For any two matrices A and B, $AB = BA$ is always true.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): If matrix A is of order $2 \times 3$ and matrix B is of order $3 \times 2$, then the product matrix AB is of order $2 \times 2$.

Reason (R): If A is of order $m \times n$ and B is of order $n \times p$, the product AB is of order $m \times p$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): A square matrix is a matrix where the number of rows is equal to the number of columns.

Reason (R): The identity matrix is a type of square matrix.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): The product of a zero matrix and any other matrix (for which the product is defined) is always the zero matrix.

Reason (R): Multiplying any number by zero results in zero.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Matrices: Properties and Advanced Operations

Question 1. Assertion (A): The transpose of a matrix A is obtained by interchanging its rows and columns.

Reason (R): If $A = (a_{ij})$, then $A' = (a_{ji})$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): If $A$ is a square matrix such that $A = A'$, then A is a symmetric matrix.

Reason (R): This is the definition of a symmetric matrix.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): The diagonal elements of a skew-symmetric matrix are always zero.

Reason (R): For a skew-symmetric matrix, $A' = -A$, which implies $a_{ii} = -a_{ii}$ for diagonal elements.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): For any square matrix A, $A+A'$ is a symmetric matrix.

Reason (R): $(A+A')' = A' + (A')' = A' + A = A+A'$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): An invertible matrix is also called a non-singular matrix.

Reason (R): A non-singular matrix is a square matrix whose determinant is non-zero, and its inverse exists.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Determinants and Adjoint

Question 1. Assertion (A): The determinant of the matrix $\begin{pmatrix} 2 & 4 \\ 1 & 2 \end{pmatrix}$ is 0.

Reason (R): In the given matrix, the first column is twice the second column, a linear dependency makes the determinant zero.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): If A and B are square matrices of the same order, then $\det(AB) = \det(A) \det(B)$.

Reason (R): The determinant of a product of matrices is the product of their determinants.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): The area of a triangle with vertices $(1, 1), (2, 2), (3, 3)$ is 0.

Reason (R): If the three vertices of a triangle are collinear, the area of the triangle is zero.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): The adjoint of a $2 \times 2$ matrix $A = \begin{pmatrix} a & b \\ c & d \end{pmatrix}$ is $\begin{pmatrix} d & -b \\ -c & a \end{pmatrix}$.

Reason (R): The adjoint of a matrix is the transpose of its cofactor matrix.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): If A is a square matrix, then $A \cdot \text{adj}(A) = \text{adj}(A) \cdot A = |A| I$.

Reason (R): This is a fundamental property relating a matrix, its adjoint, and its determinant.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Inverse of a Matrix and Systems of Equations

Question 1. Assertion (A): A square matrix A has an inverse if and only if its determinant is non-zero.

Reason (R): If $|A| \neq 0$, the matrix is singular and its inverse exists.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): The solution to a system of linear equations $AX=B$, where A is the coefficient matrix and $|A| \neq 0$, is given by $X = A^{-1}B$.

Reason (R): Multiplying the matrix equation $AX=B$ by $A^{-1}$ on the left side gives $A^{-1}(AX) = A^{-1}B$, which simplifies to $X = A^{-1}B$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): Cramer's Rule is applicable to solve any system of linear equations $AX=B$.

Reason (R): Cramer's Rule requires the coefficient matrix A to be square and its determinant $|A|$ to be non-zero.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): If $|A|=0$ for a system $AX=B$, the system cannot have a unique solution.

Reason (R): If $|A|=0$, the matrix A is singular, and the equation $AX=B$ cannot be solved by multiplying by $A^{-1}$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): The homogeneous system $AX=O$ ($B=O$) has a non-trivial solution if $|A|=0$.

Reason (R): If $|A|=0$, the matrix A is singular, and there are linear dependencies among the rows/columns, leading to infinite solutions (including non-trivial ones for $B=O$).

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:



Applications of Algebraic Equations in Word Problems

Question 1. Assertion (A): A problem involving finding the speeds of a boat in still water and a stream, given upstream and downstream times/distances, can be solved using a system of linear equations.

Reason (R): Upstream and downstream speeds are linear combinations of the boat's speed and the stream's speed ($u-v$ and $u+v$).

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 2. Assertion (A): A word problem about finding a two-digit number where the digits are reversed after adding a value often leads to a linear equation in one variable.

Reason (R): If the digits are $t$ and $u$, the number is $10t+u$. The reversed number is $10u+t$. Relationships between these are typically linear equations in $t$ and $u$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 3. Assertion (A): A problem involving the time taken by pipes to fill or empty a tank can often be solved using equations based on their filling/emptying rates.

Reason (R): If a pipe fills a tank in $T$ units of time, its rate of filling is $1/T$ of the tank per unit of time.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 4. Assertion (A): A word problem about finding two positive numbers given the sum of their squares and the difference of their squares can be solved using a system of two equations involving squares of variables.

Reason (R): Let the numbers be $x$ and $y$. The given conditions translate to equations like $x^2+y^2 = S$ and $x^2-y^2 = D$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer:

Question 5. Assertion (A): Problems involving price, quantity, and total cost, where one variable changes causing another to change, can often lead to quadratic equations.

Reason (R): If total cost $= \text{price} \times \text{quantity}$, and both price and quantity are expressed in terms of one variable (e.g., initial price $p$, new price $p \pm \Delta p$, initial quantity $Q = Cost/p$, new quantity $Q \mp \Delta Q = Cost/(p \pm \Delta p)$), substituting these relationships can result in a quadratic equation in $p$.

(A) Both A and R are true, and R is the correct explanation of A.

(B) Both A and R are true, but R is not the correct explanation of A.

(C) A is true, but R is false.

(D) A is false, but R is true.

Answer: