Fusion of a male gamete with egg in embryo sac is

Options

A. Autogamy
B. Synagamy
C. Double fertilisation
D. Triple fusion.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the fusion of a male gamete with an egg in the embryo sac. This is a key event in the reproductive process of plants.

2. **Identifying the Process**: The fusion of the male gamete (sperm) with the egg cell is a specific type of fertilization that occurs in plants. This process is crucial for the formation of the zygote.

3. **Defining Syngamy**: The correct term for the fusion of the male gamete with the egg is called **syngamy**. This term specifically refers to the fusion that leads to the formation of a zygote.

4. **Differentiating from Other Processes**: It is important to note that there are other types of fusions that occur during plant reproduction, such as triple fusion, where a second male gamete fuses with two polar nuclei. However, since the question specifically asks about the fusion with the egg, we focus on syngamy.

5. **Conclusion**: Therefore, the fusion of a male gamete with the egg in the embryo sac is termed **syngamy**.

**Final Answer**: The fusion of a male gamete with the egg in the embryo sac is termed **syngamy**.

---