Which of the following plants are heterosporous ?

Options

A. Selaginella, Lycopodium
B. Pteris, Adiantum
C. Psilotum, Equisetum
D. Selaginella, Salvinia

Answer

To determine which of the following plants are heterosporous, we need to understand the definition of heterospory and identify the plants mentioned in the options.

### Step-by-Step Solution:

1. **Understand Heterospory**:
- Heterosporous plants are those that produce two different types of spores: microspores (small) and megaspores (large). This is in contrast to homosporous plants, which produce only one type of spore.

2. **Identify the Options**:
- The options provided are:
- A) Selaginella and Lycopodium
- B) Pteris and Adiantum
- C) Equisetum and Silotum
- D) Selaginella and Salvinia

3. **Analyze Each Option**:
- **Option A (Selaginella and Lycopodium)**:
- Selaginella is heterosporous as it produces both microspores and megaspores.
- Lycopodium is homosporous, producing only one type of spore.
- **Option B (Pteris and Adiantum)**:
- Both Pteris and Adiantum are homosporous ferns, producing only one type of spore.
- **Option C (Equisetum and Silotum)**:
- Equisetum (horsetails) is homosporous, while Silotum is also homosporous.
- **Option D (Selaginella and Salvinia)**:
- Both Selaginella and Salvinia are heterosporous. Salvinia also produces two types of spores.

4. **Conclusion**:
- The correct answer is **Option D (Selaginella and Salvinia)**, as both of these plants are heterosporous.

### Final Answer:
The plants that are heterosporous are **Selaginella and Salvinia**.