Identify the stage of reproduction that involves three successive mitotic divisions.

Options

A. Formation of pollen grains from microspores
B. Formation of megaspores from megaspore mother cells
C. Formation of embryo sac from megaspore
D. Formation of PEN

Explanation

To identify the stage of reproduction that involves three successive mitotic divisions, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Mitosis**: Mitosis is a type of cell division that results in two daughter cells, each having the same number of chromosomes as the parent nucleus. In the context of reproduction, certain stages involve multiple rounds of mitosis.

2. **Identifying Relevant Processes**: The question mentions three successive mitotic divisions. In plant reproduction, particularly in the formation of gametes, certain processes involve multiple mitotic divisions.

3. **Analyzing the Stages**:
- **Formation of Pollen Grains from Microspores**: This involves mitosis but does not specify three divisions.
- **Formation of Megaspores from Megaspore Mother Cell**: This is primarily a meiotic process, not mitotic.
- **Formation of Embryo Sac from Megaspore**: This is the key stage. After the megaspores are formed, typically one megaspore survives and undergoes three successive mitotic divisions to form the embryo sac.

4. **Conclusion**: The correct answer is the formation of the embryo sac from the megaspore, which involves three successive mitotic divisions. This process is crucial in plant reproduction as it leads to the development of the female gametophyte.

### Final Answer:
The stage of reproduction that involves three successive mitotic divisions is the formation of the **embryo sac from the megaspore**.

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