Pneumatic bones occur in

Options

A. Amphibians
B. Reptile
C. Birds
D. Mammals

Answer

**Step-by-Step Solution:**

1. **Understanding Pneumatic Bones:**
- Pneumatic bones are characterized by being hollow and filled with air instead of bone marrow. This structural adaptation helps in reducing the overall weight of the bones.

2. **Identifying the Function of Pneumatic Bones:**
- The primary function of pneumatic bones is to lighten the body weight, which is crucial for animals that need to fly. This adaptation allows for easier movement and flight.

3. **Analyzing the Options:**
- The options provided are amphibians, reptiles, birds, and mammals.
- Amphibians and reptiles are primarily terrestrial and do not have the same need for lightweight bones as flying animals do.
- Mammals also do not typically possess pneumatic bones.

4. **Determining the Correct Answer:**
- Birds are the only group among the options that have adapted to flight and possess pneumatic bones. This adaptation is essential for their ability to fly efficiently.

5. **Conclusion:**
- Therefore, the correct answer is that pneumatic bones occur in **birds**.

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