In angiosperms, functional megaspore develops into

Options

A. embryo sac
B. ovule
C. endosperm
D. pollen sac.

Explanation

To answer the question "In angiosperms, functional megaspore develops into," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Terms**:
- First, we need to understand what a functional megaspore is. In angiosperms (flowering plants), the megasporocyte (a diploid cell) undergoes meiosis to produce four haploid megaspores. Out of these, typically only one megaspore is functional.

2. **Development Process**:
- The functional megaspore undergoes a process called **megasporangiasis**, which is the formation of megaspores in the ovule (megasporangium).
- After this, the functional megaspore goes through another process called **megagametogenesis**, where it develops into the embryo sac (the female gametophyte).

3. **Identifying the Correct Answer**:
- The question asks what the functional megaspore develops into. Based on the processes described, the correct answer is that it develops into the **embryo sac**.
- We can now evaluate the options:
- Option 1: Embryo sac - **Correct**
- Option 2: Ovule - **Incorrect**
- Option 3: Endosperm - **Incorrect**
- Option 4: Pollen sac - **Incorrect**

4. **Conclusion**:
- Therefore, the functional megaspore in angiosperms develops into the **embryo sac**.

### Final Answer:
The functional megaspore in angiosperms develops into the **embryo sac**.

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