The development of pollen grains occurs within -

Options

A. Ovary
B. Ovule
C. Megasporangium
D. Microsporangium

Answer

To determine where the development of pollen grains occurs, we need to analyze the options provided: ovary, ovule, megasporangium, and microsporangium.

### Step-by-Step Solution:

1. **Understanding Pollen Grains**: Pollen grains are the male gametes in flowering plants (angiosperms). They are crucial for the process of fertilization.

2. **Location of Pollen Grain Development**: Pollen grains develop in a specific part of the flower. In flowering plants, the male reproductive structure is called the stamen, which consists of the anther and filament.

3. **Role of the Anther**: The anther is the part of the stamen that contains the pollen sacs. It is here that pollen grains are produced.

4. **Microsporangium**: Within the anther, there are structures called microsporangia. These are specialized tissues where the development of pollen grains occurs through the process of meiosis.

5. **Conclusion**: Therefore, the correct answer to the question is that the development of pollen grains occurs within the **microsporangium**.

### Final Answer:
The development of pollen grains occurs within the **microsporangium**.

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