Holoblastic cleavage may occur in eggs which are

Options

A. Oligolecithal only
B. Mesolecithal only
C. Macrolecithal only
D. Oligolecithal and mesolecithal both

Explanation

### Step-by-Step Solution:

1. **Understanding Holoblastic Cleavage**:
- Holoblastic cleavage is a type of embryonic development where the entire egg is divided into smaller cells (blastomeres). This means that the cleavage furrow passes through the entire egg, resulting in equal division.

2. **Types of Eggs**:
- Eggs can be classified based on the amount and distribution of yolk. The three main categories are:
- **Oligolacital**: Eggs with a small amount of yolk.
- **Mesolacital**: Eggs with a moderate amount of yolk.
- **Macrolacital**: Eggs with a large amount of yolk.

3. **Occurrence of Holoblastic Cleavage**:
- Holoblastic cleavage typically occurs in eggs that are either oligolacital or mesolacital. This is because these types of eggs have enough cytoplasm to allow for complete division during cleavage.

4. **Conclusion**:
- Therefore, holoblastic cleavage may occur in eggs which are oligolacital or mesolacital.

### Final Answer:
Holoblastic cleavage may occur in eggs which are oligolacital or mesolacital.

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