Embryo sac is

Options

A. Microgametophyte
B. Microsporangium
C. Megagametophyte
D. Megasporangium.

Answer

To solve the question "Embryo sac is," we need to analyze the options provided and understand the definitions of the terms involved.

### Step-by-Step Solution:

1. **Understanding the Embryo Sac**:
- The embryo sac is a crucial structure in the reproductive process of flowering plants (angiosperms). It is the female gametophyte that develops within the ovule.

2. **Identifying the Correct Option**:
- The options given are:
- A) Micro gametophyte
- B) Microsporangium
- C) Megagametophyte
- D) Megasporangium

3. **Analyzing Each Option**:
- **A) Micro gametophyte**: This refers to the male gametophyte, which produces male gametes (pollen grains). This is not related to the embryo sac, so this option is incorrect.
- **B) Microsporangium**: This is a structure that produces microspores, which develop into male gametophytes. This is also not related to the embryo sac, so this option is incorrect.
- **C) Megagametophyte**: The embryo sac is indeed the megagametophyte. It is formed from the megaspores and contains eight nuclei and seven cells. This option is correct.
- **D) Megasporangium**: This structure gives rise to megaspores, which develop into the megagametophyte (embryo sac). However, it is not the same as the embryo sac itself, so this option is incorrect.

4. **Conclusion**:
- Based on the analysis, the correct answer is **C) Megagametophyte**.

### Final Answer:
The embryo sac is a **megagametophyte**.

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