The tympanic cavity is connected with the pharynx by

Options

A. Bartholin's ducts
B. Internal nares
C. Eustachian tubes
D. None of these.

Answer

To answer the question "The tympanic cavity is connected with the pharynx by," we will analyze the options provided and determine the correct one step by step.

### Step-by-Step Solution:

1. **Understanding the Tympanic Cavity**:
- The tympanic cavity, also known as the middle ear, is an air-filled space located behind the eardrum. It plays a crucial role in hearing by transmitting sound vibrations from the outer ear to the inner ear.

2. **Identifying the Connection to the Pharynx**:
- The question asks how the tympanic cavity connects to the pharynx. The pharynx is a part of the throat that is involved in both the respiratory and digestive systems.

3. **Evaluating the Options**:
- **Option A: Bartholin's duct**: This structure is part of the female reproductive system and is not related to the ear or pharynx. Therefore, this option is incorrect.
- **Option B: Internal nares**: These are internal nostrils found in some fish and are not relevant to the human ear anatomy. Hence, this option is also incorrect.
- **Option C: Eustachian tubes**: These are the canals that connect the middle ear (tympanic cavity) to the pharynx. They help equalize pressure in the ear and drain fluid. This option is likely to be correct.
- **Option D: None of these**: Since we have identified Eustachian tubes as a valid connection, this option is incorrect.

4. **Conclusion**:
- After evaluating all the options, the correct answer is **C: Eustachian tubes**. These tubes connect the tympanic cavity to the pharynx, allowing for pressure regulation and drainage.

### Final Answer:
The tympanic cavity is connected with the pharynx by **Eustachian tubes**.

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