Assertion :- When a rubber band is stretched entropy increases.
Reason :- During expansion entropy increases.

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is False.
D. If both Assertion & Reason are false.

Answer

To solve the question, we need to analyze both the assertion and the reason given.

### Step 1: Understand the Assertion
The assertion states that "When a rubber band is stretched, entropy increases."

- **Analysis**: When a rubber band is stretched, the long polymer chains within the rubber band become more aligned. This alignment reduces the randomness of the molecular arrangement. Since entropy is a measure of disorder or randomness, the stretching of the rubber band leads to a decrease in entropy, not an increase.

### Step 2: Understand the Reason
The reason states that "During expansion, entropy increases."

- **Analysis**: In general, when a system expands, the molecules have more space to move around, which typically increases the randomness of the system. However, in the specific case of a rubber band being stretched, the alignment of the polymers reduces randomness. Therefore, while the reason may hold true for many systems, it does not apply to the rubber band scenario.

### Step 3: Conclusion
Both the assertion and the reason are incorrect in the context of a rubber band being stretched.

- **Final Answer**: Therefore, the correct answer is that both the assertion and the reason are false.

### Summary of the Solution:
1. **Assertion**: False - Stretching a rubber band decreases entropy due to increased alignment of polymers.
2. **Reason**: False - While expansion generally increases entropy, in the case of a rubber band, stretching decreases randomness and thus decreases entropy.
3. **Correct Answer**: Both assertion and reason are false.

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