Vitamin D is produced in human body by

Options

A. Muscles
B. Nerves
C. Skin
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding Vitamin D Production**: Vitamin D is a crucial nutrient that acts as a hormone in the body. It plays a significant role in calcium absorption and bone health.

2. **Sources of Vitamin D**: The human body can produce Vitamin D when the skin is exposed to sunlight, specifically ultraviolet B (UVB) rays.

3. **Role of the Skin**: When UVB rays hit the skin, a chemical reaction occurs. Cholesterol present in the skin cells is converted into Vitamin D3 (cholecalciferol).

4. **Types of Vitamin D**: There are two main forms of Vitamin D relevant to human health:
- Vitamin D2 (ergocalciferol), which is obtained from certain fungi and yeast.
- Vitamin D3 (cholecalciferol), which is synthesized in the skin upon sunlight exposure.

5. **Conclusion**: Given the options (muscles, nerves, skin, none of these), the correct answer is that Vitamin D is produced in the human body by the skin.

**Final Answer**: Vitamin D is produced in the human body by the skin.

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