Assertion :- Meiosis-l is most significant phenomenon from evolution point of view.
Reason:- Meiosis-l leads to reduction in chromosome so that consistancy of chromosome can be maintained.

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 analyze the given assertion and reason, we will break down the statements and evaluate their correctness step by step.

### Step 1: Evaluate the Assertion
**Assertion:** Meiosis-I is the most significant phenomenon from an evolutionary point of view.

- **Explanation:** Meiosis-I is indeed significant for evolution because it introduces genetic variation through processes such as crossing over during prophase I. This genetic variation is crucial for natural selection and evolution, as it provides a population with diverse traits that may enhance survival and reproduction.

### Step 2: Evaluate the Reason
**Reason:** Meiosis-I leads to a reduction in chromosome number so that the consistency of chromosomes can be maintained.

- **Explanation:** While it is true that meiosis results in a reduction of chromosome number (from diploid to haploid), the reason provided does not accurately explain the significance of meiosis-I in terms of evolution. The primary evolutionary significance of meiosis-I lies in the genetic variation it creates, not merely in the reduction of chromosome number.

### Step 3: Determine the Relationship between Assertion and Reason
- The assertion is true, as meiosis-I is significant for evolution due to genetic variation.
- The reason is also true, as meiosis-I does lead to a reduction in chromosome number, but it does not serve as a correct explanation for the assertion regarding evolutionary significance.

### Conclusion
Based on the evaluations:
- The assertion is true.
- The reason is true but does not correctly explain the assertion.

Thus, the correct answer is that both the assertion and reason are true, but the reason is not the correct explanation of the assertion.

### Final Answer
**Correct Option:** 2. Both assertion and reason are true, but reason is not the correct explanation of assertion.

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