Largest cell in embryo sac

Options

A. Has two polar nuclei
B. Contributes precursor of triple fusion and generative fertilization both
C. Also consists synergids at chalazal end
D. Is involved in syngamy

Answer

### Step-by-Step Solution

1. **Identify the Question**: The question asks for the largest cell in the embryo sac.

2. **Understand the Embryo Sac Structure**: The embryo sac is a structure found within the ovule of flowering plants. It contains several cells, including the egg cell, synergids, antipodal cells, and the central cell.

3. **Determine the Largest Cell**: Among these cells, the central cell is recognized as the largest cell in the embryo sac.

4. **Characteristics of the Central Cell**: The central cell is located in the center of the embryo sac and is unique because it contains two polar nuclei.

5. **Function of the Central Cell**: The two polar nuclei in the central cell play a crucial role in fertilization. They fuse with a male gamete (sperm cell) during the process of fertilization to form the endosperm.

6. **Understanding Triple Fusion**: This fusion of the two polar nuclei with a male gamete is referred to as triple fusion, resulting in a triploid structure known as the endosperm, which is essential for nourishing the developing embryo.

7. **Conclusion**: Therefore, the largest cell in the embryo sac is the central cell, which contains two polar nuclei.

### Final Answer
The largest cell in the embryo sac is the **central cell**, which has **two polar nuclei**.

---