Which of the following is heterosporous

Options

A. Adiantum
B. Equisetum
C. Dryopteris
D. Salvinia

Answer

To determine which of the following options is heterosporous, we need to understand the definitions of heterosporous and homosporous plants.

### Step-by-Step Solution:

1. **Understand Heterospory**: Heterospory refers to the production of two different types of spores by a plant: microspores (male) and megaspores (female). These spores differ in size and function.

2. **Understand Homospory**: In contrast, homospory is when a plant produces only one type of spore, which is typically of the same size and shape.

3. **Analyze the Options**:
- **Option A: Adiantum** - This is a genus of ferns that produces only one type of spore (homosporous).
- **Option B: Equisetum** - This is a genus of horsetails, also producing only one type of spore (homosporous).
- **Option C: Dryopteris** - This is another genus of ferns that is homosporous, producing only one type of spore.
- **Option D: Salvinia** - This is a genus of water ferns that produces two types of spores (heterosporous).

4. **Conclusion**: Based on the definitions and analysis of the options, Salvinia (Option D) is the only plant listed that is heterosporous.

### Final Answer:
The correct answer is **Option D: Salvinia**.

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