Air enters into the lungs through the

Options

A. Skin
B. Buccal cavity
C. Mouth
D. cloaca

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks through which structure does air enter the lungs. We need to identify the correct anatomical pathway for respiration in frogs.

2. **Identifying Types of Respiration**: In frogs, respiration occurs through three main types:
- Cutaneous respiration (through the skin)
- Buccopharyngeal respiration (through the buccal cavity)
- Pulmonary respiration (through the lungs)

3. **Focusing on Pulmonary Respiration**: The question specifically pertains to pulmonary respiration, which involves the lungs.

4. **Pathway of Air Entry**:
- Air enters the nostrils first.
- From the nostrils, it moves into the buccal cavity.
- Finally, the air travels from the buccal cavity into the lungs.

5. **Evaluating the Options**:
- **Skin**: Incorrect, as it is involved in cutaneous respiration.
- **Buccal Cavity**: This is the correct answer as it is part of the pathway for air entering the lungs.
- **Mouth**: Incorrect, as it is not the specific term used in the context of frog respiration.
- **Cloaca**: Incorrect, as it is related to excretion and not respiration.

6. **Conclusion**: The correct answer is the **buccal cavity** (Option B), as it is the structure through which air enters the lungs after passing through the nostrils.

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