The cartilaginous structure/s ,lined with mucous membrane is/ are

Options

A. Larynx
B. Pharynx
C. Trachea
D. Both (a) and (c)

Answer

To solve the question regarding the cartilaginous structures lined with mucous membrane, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Structures**: We need to identify which of the given structures (larynx, pharynx, trachea) are cartilaginous and lined with mucous membrane.

2. **Analyze Each Structure**:
- **Larynx**: The larynx is a cartilaginous structure that serves as the voice box and is indeed lined with a mucous membrane. This makes it a valid option.
- **Pharynx**: The pharynx is primarily a muscular structure and does not have a significant cartilaginous component. It is not considered a cartilaginous structure, so it does not qualify.
- **Trachea**: The trachea, also known as the windpipe, is a cartilaginous tube that is lined with a mucous membrane. This makes it another valid option.

3. **Conclusion**: Based on the analysis, the structures that are cartilaginous and lined with mucous membrane are the larynx and trachea. Therefore, the correct answer is "both A and C".

### Final Answer:
The cartilaginous structures lined with mucous membrane are the **larynx and trachea** (both A and C).

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