Insecticide pyrethrum is prepared from

Options

A. Vetiveria
B. Chrysanthemum
C. Tephrosia
D. Cymbopogon

Answer

**Step-by-Step Solution:**

1. **Understanding Insecticides**: Begin by defining what insecticides are. Insecticides are substances used to kill insects, which can be harmful to crops and plants.

2. **Types of Insecticides**: Recognize that insecticides can be classified into two main types: natural insecticides, which are derived from plants, and synthetic insecticides, which are manufactured in laboratories.

3. **Identifying Pyrethrum**: The question specifically asks about pyrethrum, which is known to be a natural insecticide.

4. **Source of Pyrethrum**: Research indicates that pyrethrum is derived from the flowers of a specific plant. The plant that produces pyrethrum is known as chrysanthemum.

5. **Active Component**: The active ingredient in pyrethrum is called pyrethrin, which is secreted by the flowers of the chrysanthemum plant. This compound is responsible for the insecticidal properties of pyrethrum.

6. **Mechanism of Action**: Understand how pyrethrum works. It affects the central nervous system (CNS) of insects, leading to their death, making it an effective insecticide.

7. **Evaluating Options**: Look at the options provided:
- Option 1: Vetiveria - Incorrect
- Option 2: Chrysanthemum - Correct
- Option 3: Tephrosia - Incorrect
- Option 4: Cymbopogon - Incorrect

8. **Conclusion**: Based on the analysis, the correct answer to the question is option 2, chrysanthemum.

**Final Answer**: Insecticide pyrethrum is prepared from **chrysanthemum**.

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