The structure of frog that acts as aquatic respiratory organ is 

Options

A. buccopharynegeal cavity
B. lungs
C. skin
D. none

Answer

To determine the structure of a frog that acts as an aquatic respiratory organ, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the structure in frogs that functions as a respiratory organ specifically in an aquatic environment.

2. **Identify the Options**: The options provided are:
- A) Buccal cavity
- B) Lungs
- C) Skin
- D) None of the above

3. **Analyze Each Option**:
- **Buccal Cavity**: This cavity is involved in the respiration process but primarily serves as a space for air intake and does not directly facilitate gas exchange in water.
- **Lungs**: Frogs do have lungs, but these are primarily used for respiration in terrestrial (land) environments, not in water.
- **Skin**: Frogs can respire through their skin, especially when submerged in water. The skin allows for the diffusion of dissolved oxygen directly into the bloodstream.

4. **Focus on Aquatic Respiration**: Since the question specifically asks about respiration in water, we need to consider which structure is primarily responsible for this. In frogs, the skin is the main organ that facilitates respiration in an aquatic environment.

5. **Conclusion**: Based on the analysis, the structure of the frog that acts as an aquatic respiratory organ is the **skin**.

### Final Answer:
The structure of the frog that acts as an aquatic respiratory organ is the **skin**.

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