Ocelli are present at the base of the 

Options

A. maxilla
B. antenna
C. mandible
D. compound eye

Answer

**Step-by-Step Solution:**

1. **Understanding Ocelli**: Ocelli are simple eyes found in certain insects, including cockroaches. They are primarily photoreceptor organs that help in detecting light.

2. **Location of Ocelli**: In cockroaches, ocelli are located at the base of the antennae. This is crucial for their function as they help the insect respond to light stimuli.

3. **Identifying Other Structures**: The question provides multiple options: Maxilla, Antenna, Mandible, and Compound Eye. It’s important to differentiate between these structures:
- **Maxilla**: Part of the mouthparts used for manipulation of food.
- **Mandible**: Another part of the mouth used for biting and chewing.
- **Compound Eye**: Composed of multiple ommatidia, providing a mosaic vision.

4. **Eliminating Incorrect Options**:
- Maxilla and Mandible are parts of the mouth and do not have ocelli.
- The Compound Eye is a complex structure and does not relate to the simple eyes (ocelli).

5. **Conclusion**: The correct answer is that ocelli are present at the base of the **Antenna**.

**Final Answer**: Ocelli are present at the base of the **Antenna**.

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