Double fertilisation (or triple fusion) leading to initiation of endosperm in angiosperms, requires

Options

A. Fusion of 4 or more polar nuclei and the second male gamete only
B. Fusion of 2 polar nuclei and second male gamete only
C. Fusion of one polar nucleus and second male gamete only
D. All these types of fusion in different types of angiosperms

Explanation

### Step-by-Step Solution:

1. **Understanding Double Fertilization**:
- In angiosperms, double fertilization refers to the process where one sperm cell fertilizes the egg cell to form the zygote, while another sperm cell fuses with two polar nuclei to form the endosperm.

2. **Components Involved**:
- The process involves two main components:
- The egg cell (which is fertilized to form the zygote).
- The polar nuclei (which are involved in forming the endosperm).

3. **Identifying the Fusions**:
- The first fusion occurs between one male gamete (sperm) and the egg cell, resulting in the formation of the zygote.
- The second fusion occurs between the second male gamete and the two polar nuclei, leading to the formation of the triploid primary endosperm nucleus.

4. **Conclusion**:
- Therefore, for double fertilization and the initiation of endosperm in angiosperms, it requires the fusion of two polar nuclei and the second male gamete only.

5. **Final Answer**:
- The correct option is: **Fusion of two polar nuclei and the second male gamete only**.