Which of the following is known as 'cochlear duct' ?

Options

A. Scala media
B. Scala vestibuli
C. Scala tympani
D. None of these

Answer

To solve the question "Which of the following is known as 'cochlear duct'?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Terminology**:
- The term 'cochlear duct' refers to a specific structure within the inner ear.

2. **Identify the Cochlear Duct**:
- The cochlear duct is also known as the scala media. It is a part of the cochlea, which is the spiral-shaped structure in the inner ear responsible for hearing.

3. **Location of the Cochlear Duct**:
- The cochlear duct (scala media) is situated between two other structures: the scala vestibuli and the scala tympani.

4. **Composition of the Cochlear Duct**:
- The cochlear duct is filled with a fluid called endolymph, which plays a crucial role in the process of hearing.

5. **Evaluate the Options**:
- Based on the information above, we can determine which option corresponds to the cochlear duct. The correct answer is the one that identifies the cochlear duct as the scala media.

6. **Conclusion**:
- After analyzing the definitions and the relationships between the structures, we conclude that the cochlear duct is known as the scala media.

### Final Answer:
The cochlear duct is known as **scala media**.

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