Assertionn : Cockroaches remain hidden and inactive during day while they become active at night.
Reasonn : Cockroaches have an outer hard skeleton which is made up of different units joined together .

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that cockroaches remain hidden and inactive during the day and become active at night. This is true as cockroaches are nocturnal creatures, meaning they are primarily active during the night.

2. **Understanding the Reason**: The reason provided is that cockroaches have an outer hard skeleton made up of different units joined together. This describes the exoskeleton of cockroaches, which is indeed true. However, the reason does not directly explain why cockroaches are nocturnal.

3. **Evaluating the Relationship**: While both the assertion and reason are true statements, the reason does not provide a correct explanation for the assertion. The nocturnal behavior of cockroaches is not due to their exoskeleton but rather their adaptation to avoid predators and conserve moisture during the day.

4. **Choosing the Correct Option**: Based on the evaluation:
- Option 1: Both assertion and reason are true, and reason is a correct explanation of assertion - **Incorrect**.
- Option 2: Both assertion and reason are true, and reason is not the correct explanation of assertion - **Correct**.
- Option 3: Assertion is true and reason is false - **Incorrect**.
- Option 4: Both assertion and reason are false - **Incorrect**.

Thus, the correct answer is **Option 2**.

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