Which one of the following is used as biological insecticide?

Options

A. Tiger beetle
B. Caterpillar
C. Silkmoth
D. Mazra poka

Answer

**Step-by-Step Solution:**

1. **Understanding Biological Insecticides**: Biological insecticides are natural organisms or substances derived from organisms that are used to control pest populations. They are environmentally friendly alternatives to chemical insecticides.

2. **Evaluating the Options**: The options given are:
- Tiger beetle
- Caterpillar
- Silk moth
- Musara pocahill

3. **Identifying the Correct Option**:
- **Tiger Beetle**: This is a predatory insect that feeds on various soil-dwelling pests, including caterpillars, wireworms, maggots, ants, aphids, and slugs. By preying on these pests, tiger beetles help reduce their populations in agricultural ecosystems, making them a biological insecticide.
- **Caterpillar**: This is a larval stage of moths and butterflies and is known to be a pest itself, causing harm to crops.
- **Silk Moth**: This is primarily known for silk production and is not used as an insecticide.
- **Musara pocahill**: This option is not widely recognized as a biological insecticide.

4. **Conclusion**: Based on the evaluation, the correct answer is the **Tiger Beetle**, as it acts as a biological insecticide by preying on harmful insects in the agro ecosystem.

**Final Answer**: Tiger beetle

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