Grey crescent develops in

Options

A. Eye of Frog
B. Fertilised egg of Frog
C. Brain of Rabbit
D. Eye of Cockroach.

Answer

**Step-by-Step Solution:**

1. **Understanding the Grey Crescent**: The grey crescent is a crescent-shaped area that appears on the surface of amphibian eggs. It is characterized by its grey color.

2. **Location of the Grey Crescent**: The grey crescent develops on the opposite side of the egg from where the sperm enters. This is crucial for the development of the embryo.

3. **Cause of Development**: The formation of the grey crescent is a result of cytoplasmic movement within the egg, which is stimulated by the entry of the sperm. This indicates that the grey crescent is related to fertilization.

4. **Identifying the Correct Option**: Among the options provided:
- Eye of frog: This is not where the grey crescent develops.
- Fertilized egg of frog: This is the correct location for the grey crescent.
- Brain of rabbit: This is not related to amphibians.
- Eye of cockroach: This is also not relevant to the grey crescent.

5. **Conclusion**: Since the grey crescent is a feature that develops in amphibians, and the only amphibian listed in the options is the frog, the grey crescent develops in the fertilized egg of the frog.

**Final Answer**: Grey crescent develops in the fertilized egg of frog.

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