Assertion : Plants having odd number of sets of chromosomes are fertile .
Reason : Plants having even number of sets of chromosomes are sterile.

Options

A. If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion, then mark (1)
B. If both Assertion and Reason are true ,but the Reason is not the correct explanation of the Assertion, then mark (2).
C. If Assertion is true, but Reason is false , then mark (3)
D. If both Assertion and Reason are false. , then mark (4)

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion and Reason:**
- The assertion states that "Plants having an odd number of sets of chromosomes are fertile."
- The reason states that "Plants having an even number of sets of chromosomes are sterile."

2. **Analyzing the Assertion:**
- Plants with an odd number of chromosome sets (e.g., triploids) are generally considered infertile. This is due to the uneven distribution of chromosomes during meiosis, which leads to issues in gamete formation.

3. **Analyzing the Reason:**
- The reason claims that plants with an even number of chromosome sets (e.g., diploids, tetraploids) are sterile. However, this is not accurate. In general, plants with an even number of chromosome sets are more likely to be fertile because they can undergo proper meiosis and produce viable gametes.

4. **Conclusion:**
- Both the assertion and the reason are incorrect. Therefore, the correct answer is that both the assertion and reason are false.

**Final Answer:**
Both the assertion and the reason are false.

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