Assertion: Cleistogamous flowers are invariably autogamous. Reason : These flowers do not open at all

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.

Answer

**Step-by-Step Solution:**

1. **Understanding the Terms:**
- **Autogamous Flowers:** These are flowers that undergo autogamy, which is a type of self-pollination. In autogamy, pollen from the anther of a flower fertilizes the ovule of the same flower.
- **Cleistogamous Flowers:** These are a specific type of flower that do not open at all, which means they remain closed throughout their life cycle.

2. **Analyzing the Assertion:**
- The assertion states that "Cleistogamous flowers are invariably autogamous." This means that because cleistogamous flowers do not open, they are likely to self-pollinate.

3. **Analyzing the Reason:**
- The reason provided is that "These flowers do not open at all." This indicates that since cleistogamous flowers remain closed, the anthers and stigmas are in close proximity, facilitating self-pollination.

4. **Connecting Assertion and Reason:**
- Since cleistogamous flowers do not open, the anthers and stigmas are close together, making it highly probable for self-pollination to occur. Therefore, the assertion that cleistogamous flowers are invariably autogamous is supported by the reason given.

5. **Conclusion:**
- Both the assertion and the reason are correct, and the reason correctly explains the assertion. Thus, the correct answer is that both the assertion and reason are true, and the reason accurately supports the assertion.

**Final Answer:** Both assertion and reason are correct, and the reason correctly explains the assertion.

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