Eustachian tube connects :

Options

A. Left atrium with right atrium
B. Left ventricles with right ventricle
C. Middle ear with external ear
D. Middle car cavity with pharynx

Answer

**Step-by-Step Solution:**

1. **Understanding the Eustachian Tube**: The Eustachian tube is a canal in the human body that plays a crucial role in connecting different parts of the ear and throat.

2. **Identifying the Connection**: The primary function of the Eustachian tube is to connect the middle ear cavity to the nasopharynx. The nasopharynx is the upper part of the throat that lies behind the nose.

3. **Evaluating the Options**:
- Option 1: "Left with right" - This option is incorrect as it does not relate to the Eustachian tube.
- Option 2: "Left with right atrium and left ventricle with a right ventricle" - This option is also incorrect as it pertains to the heart, not the Eustachian tube.
- Option 3: "Middle ear with external ear" - This option is incorrect because the Eustachian tube does not connect the middle ear to the external ear.
- Option 4: "Middle ear cavity with pharynx" - This option is correct as it accurately describes the connection made by the Eustachian tube.

4. **Conclusion**: The Eustachian tube connects the middle ear cavity with the pharynx (nasopharynx).

**Final Answer**: The Eustachian tube connects the middle ear cavity with the pharynx.

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