A : When a body is charged, its mass changes.
R : Charge is quantized.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2).
C. If Assertion is true statement but Reason is false, then mark (3).
D. If both Assertion and Reason are false statements, then mark (4).

Answer

To solve the question, we need to analyze both the assertion (A) and the reason (R) given in the problem.

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that when a body is charged, its mass changes.
- This can be understood by considering that charge is carried by electrons. When a body gains or loses electrons, its mass will change accordingly. For example, if a body loses electrons, it will lose a small amount of mass equivalent to the mass of the electrons removed. Conversely, if it gains electrons, it will gain mass.

2. **Understanding the Reason (R)**:
- The reason states that charge is quantized.
- Charge is quantized means that charge exists in discrete amounts, specifically in integral multiples of the elementary charge (the charge of a single electron, denoted as 'e'). Thus, you cannot have a fraction of an electron's charge; charges can only be whole numbers of 'e'.

3. **Analyzing the Relationship between A and R**:
- The assertion (A) is true because the mass of a charged body changes when electrons are added or removed.
- The reason (R) is also true because charge is indeed quantized, and this quantization is a fundamental property of electric charge.

4. **Determining the Explanation**:
- While both statements are true, the reason (R) does not directly explain the assertion (A). The quantization of charge explains how charge is transferred but does not explain why the mass of the body changes when it is charged.

5. **Conclusion**:
- Both the assertion and the reason are true, but the reason does not provide a correct explanation for the assertion. Therefore, the correct answer is that both A and R are true, but R is not the correct explanation of A.

### Final Answer:
Both assertion and reason are true, but the reason is not the correct explanation of the assertion.

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