Rejection of transplanted organ is prevented by regular use of

Options

A. Cyclosporin
B. Calcitonin
C. Thrombin
D. Pyroxin

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the substance that prevents the rejection of transplanted organs. Rejection occurs when the recipient's immune system identifies the transplanted organ as foreign and attacks it.

2. **Identifying the Options**: The options given are:
- A) Cyclosporine
- B) Calcitonin
- C) Thrombin
- D) Pyroxene

3. **Analyzing Each Option**:
- **Cyclosporine**: This is an immunosuppressant drug that inhibits T-cell activity, which is crucial in preventing the immune system from attacking the transplanted organ. It is commonly used in organ transplantation.
- **Calcitonin**: This hormone is involved in calcium regulation and is used to treat bone diseases, not for preventing organ rejection.
- **Thrombin**: This is a protein involved in blood coagulation and is used to stop bleeding, not related to organ transplantation.
- **Pyroxene**: This is a vitamin B6 derivative used to treat deficiencies, not for organ rejection.

4. **Conclusion**: Based on the analysis, the correct answer is **Cyclosporine** as it is specifically used to prevent the rejection of transplanted organs by suppressing the immune response.

5. **Final Answer**: The rejection of transplanted organ is prevented by regular use of **Cyclosporine**.

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