Assertion:During anaphase-II, the chromatids of a cromosome separate.
Reason: Centromere of a mitotic chromosome divides during anaphase.

Options

A. IF both Assertion & Reason are true and the reason followed 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 statement then mark (4).

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that during anaphase II, the chromatids of a chromosome separate.
- Anaphase II is a stage in meiosis, which follows meiosis I and is part of the second meiotic division.

2. **Understanding the Reason:**
- The reason provided is that the centromere of a mitotic chromosome divides during anaphase.
- This refers to the process that occurs during mitosis, specifically during anaphase, where the centromeres of chromosomes divide, allowing sister chromatids to separate.

3. **Analyzing Anaphase II:**
- In anaphase II of meiosis, the centromeres of the chromosomes divide, which leads to the separation of sister chromatids. This is similar to what happens in mitotic anaphase, but it occurs in a meiotic context.

4. **Analyzing the Reason in Relation to the Assertion:**
- While both the assertion and reason are true, the reason given (centromere division in mitosis) does not directly explain the assertion about anaphase II in meiosis.
- The assertion is specifically about meiosis, while the reason pertains to mitosis.

5. **Conclusion:**
- Therefore, both the assertion and reason are true, but the reason does not correctly explain the assertion.
- The correct option is that both the assertion and reason are true, but the reason is not the correct explanation for the assertion.

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

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