Tympanic membrane is streched over a cartilaginous ring called

Options

A. Tympnaicus annulus
B. Columella auris
C. Stapes
D. Fenestra ovalis

Answer

To answer the question "Tympanic membrane is stretched over a cartilaginous ring called," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Tympanic Membrane**: The tympanic membrane, commonly known as the eardrum, is a thin membrane that separates the outer ear from the middle ear. It plays a crucial role in hearing by vibrating in response to sound waves.

2. **Location of the Tympanic Membrane**: In frogs, the tympanic membrane is located in the middle ear cavity. This cavity is bounded externally by the tympanic membrane itself.

3. **Cartilaginous Ring**: The tympanic membrane is not just floating; it is held in place and slightly stretched over a specific structure. This structure is a cartilaginous ring.

4. **Identifying the Cartilaginous Ring**: The cartilaginous ring over which the tympanic membrane is stretched is known as the "Campagnius annulus." This term specifically refers to the ring of cartilage that supports the tympanic membrane.

5. **Conclusion**: Therefore, the correct answer to the question is that the tympanic membrane is stretched over a cartilaginous ring called the "Campagnius annulus."

### Final Answer:
The tympanic membrane is stretched over a cartilaginous ring called the **Campagnius annulus**.

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