All are post-fertilisation events, except

Options

A. Proliferation of ovary wall into pericarp
B. Ovule matures into seed
C. Development of embryo sac
D. Integuments of ovule become seed coat

Answer

To solve the question "All are post-fertilization events, except," we need to analyze each of the provided options and determine which one does not belong to the category of post-fertilization events.

### Step-by-Step Solution:

1. **Understand Post-Fertilization Events**: Post-fertilization events refer to the processes that occur after fertilization has taken place. This includes the development of the zygote, formation of seeds, and changes in the ovary.

2. **Analyze Option 1: Proliferation of ovary wall into pericarp**:
- This event occurs after fertilization when the ovary wall develops into the pericarp (the fruit wall).
- **Conclusion**: This is a post-fertilization event.

3. **Analyze Option 2: Ovule matures into seed**:
- After fertilization, the ovule undergoes development and matures into a seed.
- **Conclusion**: This is also a post-fertilization event.

4. **Analyze Option 3: Development of embryo sac**:
- The embryo sac develops during the process of double fertilization, which occurs before the actual fertilization of the egg cell.
- **Conclusion**: This is NOT a post-fertilization event.

5. **Analyze Option 4: Integuments of ovule become seed coat**:
- After fertilization, the integuments of the ovule develop into the seed coat.
- **Conclusion**: This is a post-fertilization event.

6. **Identify the Exception**:
- From the analysis, we see that Option 3 (development of embryo sac) is the only event that does not occur after fertilization, making it the exception we are looking for.

### Final Answer:
The correct answer is **Option 3: Development of embryo sac**.

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