A small passage that permits continuity between scala vestibuli and scala tympani is

Options

A. helicotrema
B. Eustachian tube
C. cochlea
D. vestibule

Explanation

To solve the question regarding the small passage that permits continuity between the scala vestibuli and scala tympani, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Structures**: Understand that the scala vestibuli and scala tympani are parts of the inner ear, specifically within the cochlea.

2. **Understand Their Connection**: Recognize that these two scalae are connected at the apex of the cochlea. This connection is crucial for the proper functioning of the auditory system.

3. **Name the Passage**: The small canal that connects the scala vestibuli and scala tympani is known as the Helicotrema.

4. **Evaluate the Options**: If provided with multiple-choice options, identify which one corresponds to the Helicotrema. The other options (eustachian tube, cochlea, vestibule) do not serve this specific function.

5. **Conclude the Answer**: Based on the identification and evaluation, conclude that the correct answer is Helicotrema.

### Final Answer:
The small passage that permits continuity between scala vestibuli and scala tympani is called the Helicotrema.

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