Bartholin's glands are situated:

Options

A. On the sides of head of some amphibians
B. At the reduced tail end of birds
C. On either side of vagina in humans
D. On either side of vas deferens in humans

Explanation

**Step-by-Step Solution:**

1. **Understanding the Female Reproductive System:**
- The female reproductive system includes various structures such as the uterus, fallopian tubes, cervix, and vagina.

2. **Identifying the Location of Bartholin's Glands:**
- Bartholin's glands are located at the posterior end of the vagina. They are situated on either side of the vaginal opening.

3. **Function of Bartholin's Glands:**
- These glands secrete a fluid that helps to lubricate the vagina and also alters the pH from acidic to alkaline, which is important during copulation.

4. **Conclusion:**
- Therefore, Bartholin's glands are situated on either side of the vagina in the female reproductive system.

**Final Answer:**
Bartholin's glands are situated on either side of the vagina.

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