The vitamin that is useful in cancer is vitamin `:-`

Options

A. A
B. `B_(17)`
C. C
D. All of these

Answer

**Step-by-Step Solution:**

1. **Identify the Vitamins Mentioned**: The question asks which vitamin is useful in cancer. The options provided are Vitamin A, Vitamin B17, Vitamin C, and "all of these".

2. **Evaluate Vitamin A**:
- Vitamin A, particularly in the form of carotene, is found in orange and green vegetables such as carrots and sweet potatoes.
- Research indicates that carotene can protect the lungs against toxins linked to lung cancer and has protective roles against stomach cancer as well.

3. **Evaluate Vitamin B17**:
- Vitamin B17, also known as amygdalin, is recognized as an anti-tumor agent.
- It is used as an alternative cancer treatment, targeting and killing cancer cells while boosting the immune system.

4. **Evaluate Vitamin C**:
- Vitamin C is known for its antioxidant properties and its role in boosting the immune system.
- It helps suppress abnormal cell growth and prevents the spread of cancerous cells in the body.

5. **Conclusion**: Since all three vitamins (A, B17, and C) have been shown to have beneficial effects in relation to cancer, the correct answer to the question is "all of these".

**Final Answer**: The vitamin that is useful in cancer is Vitamin A, B17, and C (all of these).

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