Evolution of seed habit first started in

Options

A. Selaginella like ancestral pteridophytes
B. Psilotum like ancestral pteridophytes
C. Gymnosperms
D. Mosses

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the initial stage of seed evolution in plants. To answer this, we need to explore the characteristics of different plant groups, particularly pteridophytes.

2. **Defining Pteridophytes**: Pteridophytes are vascular plants that reproduce via spores. They can be classified into two categories based on their spore types: homosporous and heterosporous.

3. **Identifying Homosporous and Heterosporous**:
- **Homosporous**: Most pteridophytes produce one type of spore, which develops into a gametophyte that produces both male and female gametes.
- **Heterosporous**: Some pteridophytes, like Selaginella and Salvinia, produce two types of spores: microspores (small) and megaspores (large). These spores develop into male and female gametophytes, respectively.

4. **Significance of Heterospory**: The evolution of heterospory is a crucial step towards the development of seeds. In heterosporous plants, the female gametophyte remains on the parent sporophyte, allowing for the fertilization process to occur in a protected environment.

5. **Development of Seeds**: After fertilization, the zygote develops into an embryo within the female gametophyte. This retention of the gametophyte and the development of the embryo is a key characteristic of seed plants.

6. **Conclusion**: Based on the information, the evolution of seed habit first started in heterosporous pteridophytes like Selaginella. Therefore, the correct answer is **Option A: Selaginella-like ancestral pteridophyte**.

---