Pinna / external ear is found in- .

Options

A. Reptiles
B. Mammals
C. Aves
D. Insects

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the presence of the pinna or external ear in different species. We need to identify which group of animals possesses this feature.

2. **Identifying the Groups**: The four groups mentioned in the question are reptiles, mammals, birds, and insects. We need to analyze each group for the presence of an external ear.

3. **Analyzing Reptiles**:
- Reptiles do not have a prominent external ear structure. They may have ear openings, but they lack a pinna.
- Conclusion: Reptiles do not have an external ear.

4. **Analyzing Mammals**:
- Mammals are characterized by the presence of a well-defined external ear (pinna) that helps in sound localization and capturing sound waves.
- Conclusion: Mammals have an external ear.

5. **Analyzing Birds**:
- Birds do not have an external ear structure like mammals. They have ear openings covered by feathers, but no pinna.
- Conclusion: Birds do not have an external ear.

6. **Analyzing Insects**:
- Insects do not possess an external ear. They have different mechanisms for detecting sound, such as tympanal organs.
- Conclusion: Insects do not have an external ear.

7. **Final Conclusion**: Based on the analysis, the only group that possesses a pinna or external ear is mammals. Therefore, the correct answer is mammals.

**Final Answer**: The pinna/external ear is found in mammals.

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