The tympanic cavity is :

Options

A. Columella auris
B. Middle ear
C. Eustachian tube
D. Internal ear

Answer

**Step-by-Step Solution:**

1. **Understanding the Tympanic Cavity**: The tympanic cavity, also known as the middle ear, is a crucial part of the auditory system. It is an air-filled space located between the outer ear (ear canal) and the inner ear (cochlea and vestibular system).

2. **Identifying Options**: The question provides several options to identify what the tympanic cavity is. We will evaluate each option to determine the correct answer.

3. **Evaluating Option 1 (Orys)**: This option is incorrect. The term "Orys" does not relate to the tympanic cavity. In amphibians, reptiles, and birds, there is a structure that connects the tympanic membrane to the inner ear, but it is not referred to as "Orys."

4. **Evaluating Option 2 (Middle Ear)**: This option is correct. The tympanic cavity is indeed the middle ear, which is a membrane-lined space that plays a vital role in hearing by transmitting sound vibrations from the outer ear to the inner ear.

5. **Evaluating Option 3 (Eustachian Tube)**: This option is incorrect. The Eustachian tube, also known as the auditory tube, connects the middle ear to the nasopharynx and helps equalize pressure but is not the tympanic cavity itself.

6. **Evaluating Option 4 (Inner Ear)**: This option is also incorrect. The inner ear consists of the cochlea and the vestibular system, which are distinct from the tympanic cavity.

7. **Conclusion**: After evaluating all options, the correct answer is that the tympanic cavity is the middle ear.

**Final Answer**: The tympanic cavity is the middle ear.

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