Electron microscope is used for

Options

A. Viewing structure of the cell
B. Whole mount study
C. Cell division study
D. Structure of the pollen grain

Explanation

### Step-by-Step Solution:

1. **Understanding the Electron Microscope**:
- The electron microscope is a type of microscope that uses a beam of electrons to create an image of the specimen. It has a much higher magnification and resolving power compared to light microscopes.

2. **Evaluating the Options**:
- The question provides four options:
- A) Viewing structure of the cell
- B) Hole mound study
- C) Cell division study
- D) Structure of pollen grains

3. **Analyzing Each Option**:
- **Option A: Viewing structure of the cell**:
- This is a suitable use for an electron microscope due to its high magnification and resolving power, which allows for detailed examination of cellular structures and organelles.
- **Option B: Hole mound study**:
- This is not a common application for electron microscopy and can typically be studied with a light microscope.
- **Option C: Cell division study**:
- While cell division can be observed, it does not require the high resolution of an electron microscope, as it can be effectively studied using light microscopy.
- **Option D: Structure of pollen grains**:
- Pollen grains can also be studied with light microscopes, making this option less suitable for electron microscopy.

4. **Conclusion**:
- Given the analysis, the electron microscope is primarily used for viewing the structure of the cell (Option A) due to its ability to reveal the ultrastructure of cells and organelles, which is not possible with light microscopes.

5. **Final Answer**:
- The correct answer is **A) Viewing structure of the cell**.