Drugs vincristine and vinblastine used in cancer therapy are obtained from

Options

A. Ravwalfia serpentina
B. Atropa belladona
C. Catharanthus roseus
D. Withania somnifera

Answer

**Step-by-Step Solution:**

1. **Identify the Drugs**: The question mentions two specific drugs, vincristine and vinblastine, which are used in cancer therapy.

2. **Understand the Source of the Drugs**: It is important to know that vincristine and vinblastine are classified as plant alkaloids. This means they are derived from plants.

3. **Examine the Options Provided**: The options given are:
- A) Revolfa serpentina
- B) Atropa belladonna
- C) Catharanthus roseus
- D) Pithania somnifera

4. **Research the Correct Plant**: Among the options, Catharanthus roseus is known to be the source of vincristine and vinblastine. It is commonly referred to as the periwinkle plant.

5. **Confirm the Family Classification**: Catharanthus roseus belongs to the family Apocynaceae. This classification helps in confirming the identity of the plant.

6. **Conclude the Answer**: Based on the information gathered, the correct answer to the question is option C, Catharanthus roseus.

**Final Answer**: Vincristine and vinblastine used in cancer therapy are obtained from **Catharanthus roseus**.

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