Which of the following insecticides is obtained from the roots of Derris elleptica?

Options

A. Cinerin
B. Nicotine
C. Rotenone
D. Pyrethrum

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the insecticide that is derived from the roots of the plant Derris elliptica.

2. **Defining Insecticides**: Insecticides are substances used to kill insects. The term is derived from "insect" (meaning insect) and "cide" (meaning to kill).

3. **Identifying the Insecticide**: The specific insecticide obtained from the roots of Derris elliptica is known as "rotenone".

4. **Properties of Rotenone**: Rotenone is characterized as being odorless and colorless, and it has a crystalline structure.

5. **Role of Rotenone**: Besides being an insecticide, rotenone also acts as a piscicide (killing fish) and a pesticide (killing pests).

6. **Source of Rotenone**: It is important to note that rotenone can be derived not only from the roots of Derris elliptica but also from other parts of certain plants, such as seeds and stems of the plant family to which it belongs.

7. **Conclusion**: Therefore, the insecticide obtained from the roots of Derris elliptica is rotenone.

**Final Answer**: Rotenone

---