Which one 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 concept of heterospory and identify the examples provided.

### Step-by-Step Solution:

1. **Understanding Heterospory**:
- Heterospory is the production of two distinct types of spores: microspores (male) and megaspores (female). These spores develop into different types of gametophytes.

2. **Identifying the Options**:
- The question provides several options, which are likely examples of pteridophytes. We need to evaluate each option to see if it exhibits heterospory.

3. **Evaluating Each Option**:
- **Option 1: Adiantum**:
- Adiantum is a genus of ferns that is homosporous, meaning it produces only one type of spore.
- **Option 2: Equisetum**:
- Equisetum, commonly known as horsetail, is also homosporous and does not produce two types of spores.
- **Option 3: Dryopteris**:
- Dryopteris is another genus of ferns that is homosporous and produces only one type of spore.
- **Option 4: Selaginella**:
- Selaginella is a well-known example of a heterosporous plant. It produces both microspores and megaspores, leading to the formation of male and female gametophytes.

4. **Conclusion**:
- Based on the evaluation, the only heterosporous plant among the options provided is **Selaginella**. Therefore, the correct answer to the question is **Option 4: Selaginella**.