Which of the following is a water soluble vitamin ?

Options

A. Vitamin A
B. Vitamin B
C. Vitamin D
D. Vitamin D

Answer

To determine which of the following is a water-soluble vitamin, we need to analyze the options given: Vitamin A, Vitamin B, and Vitamin D.

### Step-by-Step Solution:

1. **Understanding Vitamins**: Vitamins are essential nutrients required by the body in small amounts. They play crucial roles in various bodily functions.

2. **Classification of Vitamins**: Vitamins are classified into two categories based on their solubility: water-soluble and fat-soluble.
- **Water-soluble vitamins**: These vitamins dissolve in water and are not stored in the body. They need to be consumed regularly. Examples include Vitamin C and various B vitamins.
- **Fat-soluble vitamins**: These vitamins dissolve in fats and can be stored in the body's fatty tissues. Examples include Vitamins A, D, E, and K.

3. **Analyzing the Options**:
- **Vitamin A**: This is a fat-soluble vitamin. It is important for vision, immune function, and skin health.
- **Vitamin B**: This refers to a group of water-soluble vitamins, including B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B7 (biotin), B9 (folate), and B12 (cobalamin). These vitamins are essential for energy metabolism and red blood cell formation.
- **Vitamin D**: This is also a fat-soluble vitamin. It is crucial for calcium absorption and bone health.

4. **Conclusion**: Among the options provided, Vitamin B is the only water-soluble vitamin.

### Final Answer:
**Vitamin B is a water-soluble vitamin.**

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