Cortical granules are associated with

Options

A. Oogenesis
B. Spermatogenesis
C. Cleavage
D. Fertilization.

Answer

### Step-by-Step Solution:

1. **Understanding Cortical Granules**:
- Cortical granules are specialized structures found in the cortex of the ovum (egg cell).
- They play a crucial role during the fertilization process.

2. **Role During Fertilization**:
- Upon fertilization, cortical granules migrate to the outer membrane of the zygote (the fertilized egg).
- They release their contents in a process known as the cortical reaction.

3. **Preventing Polyspermy**:
- The primary function of the cortical reaction is to prevent polyspermy, which is the fertilization of an egg by multiple sperm.
- This is essential for ensuring that the zygote has the correct number of chromosomes.

4. **Association with Fertilization**:
- Given their role in the cortical reaction and the prevention of polyspermy, it can be concluded that cortical granules are directly associated with the process of fertilization.

5. **Evaluating Options**:
- If we consider the options:
- **Oogenesis**: Incorrect, as it refers to the development of the ovum, not the role of cortical granules.
- **Spermatogenesis**: Incorrect, as it refers to the development of sperm, not related to cortical granules.
- **Cleavage**: Incorrect, as it refers to the division of cells after fertilization, not the role of cortical granules.
- Therefore, the correct association is with **fertilization**.

### Final Answer:
Cortical granules are associated with **fertilization**.

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