Find odd one with respect to the stage which occurs after most vital event of sexual life cycle of angiosperms.

Options

A. Ovule to seed development
B. Primary endosperm nucleus to endosperm development
C. Megaspore to embryo sac development
D. Zygote to embryo development

Answer

To solve the question of identifying the odd one out with respect to the stage that occurs after the most vital event of the sexual life cycle of angiosperms, we will analyze the provided statements step by step.

### Step-by-Step Solution:

1. **Understanding the Vital Event**:
- The most vital event in the sexual life cycle of angiosperms is **fertilization**. This process involves the fusion of male and female gametes.

2. **Identifying the Stages**:
- After fertilization, several developmental stages occur. We need to evaluate each statement to see if it describes a process that happens after fertilization.

3. **Analyzing Each Statement**:
- **Statement 1**: "Ovule to seed development"
- This statement is correct. After fertilization, the ovule develops into a seed.

- **Statement 2**: "Primary endosperm nucleus to endosperm development"
- This statement is also correct. The primary endosperm nucleus, formed during fertilization, develops into endosperm, which nourishes the developing zygote.

- **Statement 3**: "Megaspore to embryo sac development"
- This statement is incorrect in the context of post-fertilization events. The megaspore develops into the embryo sac before fertilization, making this a pre-fertilization event.

- **Statement 4**: "Zygote to embryo development"
- This statement is correct. The zygote, formed after fertilization, develops into the embryo.

4. **Identifying the Odd One Out**:
- From the analysis, Statements 1, 2, and 4 describe processes that occur after fertilization, while Statement 3 describes a process that occurs before fertilization. Therefore, **Statement 3** is the odd one out.

### Final Answer:
The odd one out is **Statement 3: "Megaspore to embryo sac development"**.

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