Double ventilation occurs in the lungs of

Options

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

Answer

### Step-by-Step Solution:

1. **Understanding Double Ventilation**:
- Double ventilation refers to a respiratory process where an organism can obtain fresh air during both inhalation and exhalation. This is different from the typical ventilation in humans, where fresh air is only taken in during inhalation.

2. **Identifying Organisms with Double Ventilation**:
- The question asks which organisms exhibit double ventilation. The options provided are:
- Sorpsinsa
- Amphibians
- Birds
- Reptiles
- Mammals

3. **Analyzing Each Option**:
- **Sorpsinsa**: This term does not correspond to a known class of organisms in biology.
- **Amphibians**: They typically have a simpler respiratory system and do not exhibit double ventilation.
- **Birds**: Birds have a unique respiratory system that allows them to have fresh air flow through their lungs during both inhalation and exhalation, making them the primary example of double ventilation.
- **Reptiles**: They do not have the same efficient respiratory system as birds.
- **Mammals**: Mammals, including humans, only take in fresh air during inhalation.

4. **Conclusion**:
- Based on the analysis, the only organisms that exhibit double ventilation are birds. Therefore, the correct answer is **birds**.

### Final Answer:
Double ventilation occurs in the lungs of **birds**.

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