Vitamin D is

Options

A. calciferol
B. ergosterol
C. tocoferol
D. pyridoxine

Answer

**Step-by-Step Solution:**

1. **Identify Vitamin D:**
- Vitamin D is commonly referred to as calciferol. It is essential for maintaining healthy bones and calcium levels in the body.

2. **Understand the Types of Vitamin D:**
- Vitamin D has two main forms:
- Vitamin D2 (ergocalciferol)
- Vitamin D3 (cholecalciferol)
- Both forms are important for health, but they are derived from different sources.

3. **Function of Vitamin D:**
- Vitamin D plays a crucial role in calcium absorption in the gut, which is vital for maintaining bone health.
- It is also involved in the regulation of calcium and phosphate in the body.

4. **Deficiency Effects:**
- A deficiency in Vitamin D can lead to several health issues, notably rickets in children, which is characterized by soft and weak bones.
- In adults, a deficiency can lead to osteomalacia, which also results in weakened bones.

5. **Distinguish from Other Vitamins:**
- Ergosterol is not Vitamin D; it is a sterol found in fungi and is a precursor to Vitamin D2.
- Tocopherol is Vitamin E, known for its antioxidant properties.
- Pyridoxine is Vitamin B6, which is important for metabolism and is not related to Vitamin D.

6. **Conclusion:**
- Based on the information, the correct answer to the question "What is Vitamin D?" is calciferol.

**Final Answer:**
Vitamin D is also known as calciferol.

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