Which is used to prevent bleeding?

Options

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

Answer

To answer the question "Which is used to prevent bleeding?", we will analyze the options provided: Vitamin K, Vitamin C, Vitamin A, and Vitamin B.

### Step-by-Step Solution:

1. **Identify the Role of Vitamin K**:
- Vitamin K is essential for the synthesis of certain proteins that are required for blood coagulation (clotting). It plays a crucial role in the formation of blood clots, which are necessary to stop bleeding when injuries occur.

2. **Evaluate Vitamin C**:
- Vitamin C, also known as ascorbic acid, is primarily involved in maintaining healthy tissues, skin, and bones. It does not play a direct role in the blood clotting process, so it is not used to prevent bleeding.

3. **Assess Vitamin A**:
- Vitamin A is important for vision and has a role in maintaining healthy skin and mucous membranes. It does not have any significant function in blood clotting, making it incorrect for preventing bleeding.

4. **Examine Vitamin B**:
- The Vitamin B complex consists of several vitamins that support various bodily functions, including energy metabolism and brain health. However, they do not play a role in the clotting process, thus are not involved in preventing bleeding.

5. **Conclusion**:
- Among the options provided, Vitamin K is the only vitamin that is directly involved in the prevention of bleeding due to its critical role in blood clotting.

### Final Answer:
**Vitamin K is used to prevent bleeding.**

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