List of some pteridophytes are given below.
Selagineila, Salvinia, Lycopodium, Psilotum, Dryopteris, Marsilea, Azolla, Pteridium. How many of the above plants are homosporous fern?

Options

A. Three
B. Two
C. Four
D. Five

Answer

To determine how many of the listed pteridophytes are homosporous ferns, we will analyze each plant in the list to classify them based on their spore types.

### Step-by-Step Solution:

1. **Understand the Terms**:
- **Homosporous**: Plants that produce only one type of spore, which typically develops into a bisexual gametophyte.
- **Heterosporous**: Plants that produce two types of spores: microspores (male) and megaspores (female).

2. **List of Plants**:
- Selaginella
- Salvinia
- Lycopodium
- Psilotum
- Dryopteris
- Marsilea
- Azolla
- Pteridium

3. **Identify the Type of Spores for Each Plant**:
- **Selaginella**: Heterosporous
- **Salvinia**: Heterosporous
- **Lycopodium**: Homosporous
- **Psilotum**: Homosporous
- **Dryopteris**: Homosporous (it is a true fern)
- **Marsilea**: Heterosporous
- **Azolla**: Heterosporous
- **Pteridium**: Homosporous

4. **Count the Homosporous Ferns**:
- From the analysis, the homosporous ferns identified are:
- Lycopodium
- Psilotum
- Dryopteris
- Pteridium
- Total: 4 homosporous ferns.

5. **Final Answer**:
- There are **4 homosporous ferns** in the list provided.