Assertion :- Morphology of chromosomes is most studied during metaphase of cell division.
Reason :- Complete disintegration of nuclear envelope marks the start of metaphase, second phase of mitosis.

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

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that the morphology of chromosomes is most studied during metaphase of cell division.
- This is true because during metaphase, chromosomes are highly condensed and visible under a microscope, making it easier to study their structure.

2. **Understanding the Reason:**
- The reason given is that the complete disintegration of the nuclear envelope marks the start of metaphase, which is the second phase of mitosis.
- This statement is also true. The nuclear envelope begins to break down during prophase, but it is during metaphase that it is completely disintegrated.

3. **Evaluating the Relationship:**
- While both the assertion and reason are correct, the reason does not directly explain why the morphology of chromosomes is best studied during metaphase.
- The assertion is based on the visibility and condensation of chromosomes, while the reason discusses the state of the nuclear envelope.

4. **Conclusion:**
- Both the assertion and the reason are true, but the reason is not a correct explanation for the assertion.

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

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