The bioactive molecule cyclosporin. Also used in -

Options

A. whooping cough
B. diphtheria
C. leprosy
D. organ-transplant patients

Answer

**Step-by-Step Solution:**

1. **Identify the Bioactive Molecule**: The question mentions the bioactive molecule cyclosporin. It is important to know what cyclosporin is and its origin.

2. **Understand the Source**: Cyclosporin A is derived from a fungus called *Trichoderma polysporum*. Recognizing its source can help in understanding its applications.

3. **Determine the Primary Use**: Cyclosporin A is primarily known for its immunosuppressive properties. This means it is used to suppress the immune system.

4. **Identify the Application**: The main application of cyclosporin A is in organ transplantation. It is used to prevent the body from rejecting the transplanted organ by suppressing the immune response.

5. **Review Other Options**: The question provides multiple options: whooping cough, diphtheria, leprosy, and organ transplant patients. Among these, the correct application of cyclosporin A is specifically for organ transplant patients.

6. **Conclusion**: Therefore, the bioactive molecule cyclosporin A is used in organ transplant patients as an immunosuppressant.

**Final Answer**: Cyclosporin A is used in organ transplant patients.

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