In an angiosperm, microsporangium is

Options

A. stamen
B. pollen grains
C. Ovule
D. pollen sacs

Answer

### Step-by-Step Solution:

1. **Understanding Angiosperms**: Angiosperms are flowering plants that produce seeds enclosed within a fruit. They are characterized by their reproductive structures, which include flowers.

2. **Identifying the Reproductive Parts**: In angiosperms, the flower contains both male and female reproductive organs. The male reproductive part is known as the stamen.

3. **Structure of the Stamen**: The stamen consists of two main parts: the anther and the filament. The filament is the stalk that supports the anther.

4. **Microsporangium Location**: The anther is bilobed, meaning it has two lobes, and within these lobes are structures known as pollen sacs.

5. **Definition of Microsporangium**: The pollen sacs are scientifically referred to as microsporangia. They are responsible for producing microspores.

6. **Formation of Pollen Grains**: Inside the microsporangia, microspores undergo mitosis and development to form pollen grains, which represent the male gametophyte in angiosperms.

7. **Conclusion**: Therefore, in an angiosperm, the microsporangium is essentially a pollen sac located within the anther of the stamen.

### Final Answer:
In an angiosperm, microsporangium is a pollen sac.

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