Which of the following is not a natural insecticide?

Options

A. Nicotine
B. Neem
C. Metasystox
D. Pyrethrum

Explanation

To determine which of the following is not a natural insecticide, we can analyze each option provided:

### Step 1: Identify the options
We need to look at the options given in the question. The options mentioned are:
1. Nicotine
2. Neem
3. Metastox
4. Pyrethrum

### Step 2: Define natural insecticides
Natural insecticides are substances derived from natural sources that are used to control pests. Examples include:
- **Nicotine**: Derived from tobacco plants, it is a natural insecticide.
- **Neem**: Extracted from the neem tree, it is widely used as a natural pesticide.
- **Pyrethrum**: Obtained from chrysanthemum flowers, it is also a natural insecticide.

### Step 3: Analyze Metastox
- **Metastox**: This is a synthetic insecticide, not derived from natural sources. It is used to control pests like aphids, mites, and whiteflies on various crops.

### Step 4: Conclusion
Based on the analysis, the option that is not a natural insecticide is **Metastox**.

### Final Answer:
The correct answer is **Metastox** (Option 3).

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