Fenestra ovalis is the opening of

Options

A. Air fille cavity of middle ear
B. External opening of tympanic cavity
C. Opening of auditory capsule
D. Communication between pharynx and tympanic cavity.

Answer

**Step-by-Step Solution:**

1. **Identify the Structure**: The question asks about "Fenestra ovalis," which is also known as the oval window.

2. **Understand its Location**: The oval window is located in the ear, specifically between the middle ear and the inner ear.

3. **Define its Function**: The oval window serves as an opening that allows sound vibrations from the middle ear to be transmitted into the inner ear.

4. **Relate to Ear Anatomy**: The oval window is associated with the auditory capsule, which houses important structures of the ear.

5. **Connection with Ear Ossicles**: The oval window is connected to the three tiny bones of the ear (ossicles) known as the malleus, incus, and stapes. These bones help in transmitting sound vibrations to the oval window.

6. **Final Conclusion**: Therefore, the Fenestra ovalis (oval window) is the opening of the auditory capsule, separating the middle ear from the inner ear.

**Final Answer**: Fenestra ovalis is the opening of the auditory capsule.

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