In the prothallus of a vascular cryptogam, the antherozoids and egg mature and different time As a result.

Options

A. There is high degree of sterillity.
B. One can conclude that the plant is apomictic.
C. Self fertilization is prevented.
D. There is no change in the success rate of fertilization.

Answer

### Step-by-Step Solution:

1. **Understanding Vascular Cryptogams**:
- Vascular cryptogams are plants that do not have flowers or seeds and include groups like ferns. They have vascular tissues but do not produce seeds.

2. **Prothallus Structure**:
- The prothallus is the gametophyte stage of vascular cryptogams. It is a small, flat, green structure that produces gametes (antherozoids and eggs).

3. **Maturation of Gametes**:
- In the prothallus, the male gametes (antherozoids) and female gametes (eggs) mature at different times. This asynchronous maturation is crucial for the reproductive strategy of these plants.

4. **Result of Different Maturation Times**:
- The fact that the antherozoids and eggs mature at different times leads to a phenomenon known as **outbreeding**. This means that self-fertilization is prevented.

5. **Advantages of Outbreeding**:
- By preventing self-fertilization, cross-fertilization is encouraged. This enhances genetic diversity and reduces the chances of inbreeding depression, which can occur when closely related individuals breed.

6. **Conclusion**:
- Therefore, the main result of the antherozoids and eggs maturing at different times in the prothallus of vascular cryptogams is that self-fertilization is prevented, promoting cross-fertilization.

### Final Answer:
In the prothallus of a vascular cryptogam, the antherozoids and eggs mature at different times, which prevents self-fertilization and promotes cross-fertilization.

---