Assertion: Selaginella and salvinia are homosporus.
Reason: Ovules of gymosperms are enclosed withini the ovaries.

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.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that "Selaginella and Salvinia are homosporous." To evaluate this, we need to understand what homosporous means. Homosporous plants produce only one type of spore, which can develop into a gametophyte that produces both male and female gametes.

2. **Evaluating Selaginella and Salvinia**: Both Selaginella and Salvinia are known to be heterosporous, meaning they produce two types of spores: megaspores (female) and microspores (male). This indicates that the assertion is incorrect.

3. **Understanding the Reason**: The reason states that "ovules of gymnosperms are enclosed within the ovaries." Gymnosperms, by definition, have naked seeds, meaning their ovules are not enclosed within an ovary. This statement is also incorrect.

4. **Conclusion**: Since both the assertion and the reason are incorrect, we can conclude that the correct option is that both the assertion and the reason are false.

5. **Final Answer**: The correct option is that both assertion and reason are false.

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