Columnar epithelium with stereocilia can be traced in :

Options

A. Mammary gland
B. Lungs
C. Epididymis
D. Trachea

Answer

**Step-by-Step Solution:**

1. **Understanding Stereocilia**: Stereocilia are specialized structures that are modifications of microvilli. They are non-motile and primarily function to increase the surface area for absorption.

2. **Identifying the Function**: Since stereocilia are a modification of microvilli, their main role is to enhance absorption, similar to microvilli but with a different structure.

3. **Locating Stereocilia in the Body**: Stereocilia can be traced specifically in certain parts of the male reproductive system, particularly in the epididymis and ductus deferens.

4. **Analyzing the Options**: Given the options:
- Mammary gland
- Lungs
- Epididymis
- Trachea

We need to identify which of these locations contains columnar epithelium with stereocilia.

5. **Selecting the Correct Answer**: Based on the knowledge that stereocilia are found in the epididymis and ductus deferens, the correct answer is **epididymis**.

6. **Final Answer**: Therefore, the correct answer to the question is **epididymis**.

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