Seed habit, considered an important step in evolution, is present in `:`
1 Adiantum
2 Selaginella
3 Pteris
4 Lycopodium

Options

A. Adiantum
B. Selaginella
C. Pteris
D. Lycopodium

Answer

To solve the question regarding which plant exhibits the seed habit, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: We need to identify which of the given plants has a seed habit, which is an important evolutionary step.

2. **Identify the Plant Types**: The options provided are:
- 1. Adiantum
- 2. Selaginella
- 3. Pteris
- 4. Lycopodium

3. **Classify the Plants**: All the listed plants are classified as pteridophytes, which are seedless vascular plants.

4. **Understand Seed Habit**: Seed habit refers to the production of seeds, which is a significant evolutionary advancement. Most pteridophytes are homosporous, meaning they produce one type of spore.

5. **Identify Exceptions**: Some pteridophytes exhibit heterospory, which is the production of two different types of spores (microspores and megaspores). This is a precursor to seed formation.

6. **Identify the Correct Plant**: Among the options:
- **Adiantum** (a fern) - typically homosporous.
- **Selaginella** - known for heterospory, thus showing a seed habit.
- **Pteris** (another fern) - typically homosporous.
- **Lycopodium** - also typically homosporous.

7. **Conclusion**: The only plant from the options that demonstrates a seed habit due to heterospory is **Selaginella**.

### Final Answer:
The correct answer is **2. Selaginella**.

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