Development of male gametophyte is :-

Options

A. Invivo
B. lnsitu
C. Both
D. In-vitro

Answer

**Step-by-Step Solution:**

1. **Understanding Male Gametophyte**: The male gametophyte is known as the pollen grain. It is crucial to identify what constitutes a male gametophyte in flowering plants.

2. **Location of Development**: Pollen grains develop within the anther, which is part of the stamen in flowering plants. This is an important detail as it indicates where the male gametophyte formation occurs.

3. **Defining Terms**:
- **In Vivo**: This term refers to processes or reactions that occur within a living organism. Since pollen grains develop inside the anther of the flower, this term is applicable.
- **In Situ**: This term means "in the original place" or "on site." The development of pollen grains occurs in situ, as it happens within the anther itself.
- **In Vitro**: This term refers to processes that occur outside of a living organism, typically in a controlled environment like a test tube. Since pollen grain development does not occur outside the organism, this term does not apply.

4. **Evaluating Options**:
- **Option A (In Vivo)**: Correct, as pollen grains develop inside the living plant.
- **Option B (In Situ)**: Correct, as the development occurs on site within the anther.
- **Option C (Both A and B)**: Correct, as both in vivo and in situ apply to the development of male gametophytes.
- **Option D (In Vitro)**: Incorrect, as development does not occur outside the living organism.

5. **Conclusion**: The correct answer is Option C, as both in vivo and in situ are valid descriptions of the development of male gametophytes.

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