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 statement provided and determine whether it refers to a post-fertilization event or not.

### Step-by-Step Solution:

1. **Identify the Statements**: We need to look at each statement provided in the question and categorize them as post-fertilization events or not.

2. **Evaluate the First Statement**:
- **Statement**: "Proliferation of ovary wall into pericarp."
- **Analysis**: This is a post-fertilization event because after fertilization, the ovary wall develops into the pericarp (the fruit wall).

3. **Evaluate the Second Statement**:
- **Statement**: "Ovary matures into seed."
- **Analysis**: This statement is also a post-fertilization event. After fertilization, the ovules develop into seeds.

4. **Evaluate the Third Statement**:
- **Statement**: "Development of the embryo sac."
- **Analysis**: This is NOT a post-fertilization event. The embryo sac is formed before fertilization and is part of the reproductive process leading up to fertilization.

5. **Evaluate the Fourth Statement**:
- **Statement**: "Improvement of the ovule becomes seed coat."
- **Analysis**: This is a post-fertilization event. After fertilization, the ovule develops into the seed, and its outer layers become the seed coat.

6. **Conclusion**: Based on the evaluations, the statement that is NOT a post-fertilization event is "Development of the embryo sac."

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

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