Vegetative fertilization, which involves formation of endosperm, is fusion of

Options

A. One male gamete with diploid secondary nucleus
B. Two vegetative cells
C. Two male gametes
D. Female gamete with secondary nucleus.

Answer

**Step-by-Step Solution:**

1. **Understanding Vegetative Fertilization**: Vegetative fertilization refers to a process in flowering plants where the endosperm is formed. This is crucial for the nourishment of the developing embryo.

2. **Identifying the Components**: In the context of flowering plants, the ovule contains several important components:
- One egg cell
- Two synergids
- Three antipodal cells
- Two polar nuclei (which together form the secondary nucleus)

3. **Role of Male Gametes**: During fertilization, two male gametes (sperm cells) are delivered to the ovule through the pollen tube.

4. **Process of Fertilization**:
- One male gamete fuses with the egg cell to form a diploid zygote (this process is called syngamy).
- The second male gamete fuses with the two polar nuclei (the diploid secondary nucleus) to form the triploid endosperm (3N).

5. **Conclusion**: The question asks about the fusion that leads to the formation of endosperm. Based on the above steps, the correct answer is that the endosperm is formed by the fusion of one male gamete with the diploid secondary nucleus.

6. **Final Answer**: Therefore, the correct answer is **Option A: One male gamete with the diploid secondary nucleus**.

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