Which one of the following is least persistent insecticide?

Options

A. Aldrin
B. Dieldrin
C. BHC
D. Carbamates

Answer

To determine which insecticide is the least persistent among the options given, we need to analyze each option based on their persistence in the environment.

### Step-by-Step Solution:

1. **Understand Persistence**:
- Persistence refers to how long a substance remains in the environment without breaking down. Persistent insecticides remain toxic for extended periods, affecting humans, plants, and animals.

2. **Evaluate Each Option**:
- **Aldrin**: This is a persistent organic pollutant used for soil insects and wooden structures. It does not degrade easily in the environment, making it persistent.
- **Dieldrin**: This is another persistent insecticide that is derived from Aldrin. It is also highly persistent and remains toxic in the environment.
- **BHC (Benzene Hexachloride)**: Also known as gamma-HCH, it is used as an agricultural insecticide. BHC is known to be persistent and toxic as well.
- **Carbamates**: This group of insecticides is used as sprays to kill insects. Unlike the others, carbamates are known to be less persistent in the environment. They can break down into smaller, less harmful compounds relatively quickly.

3. **Conclusion**:
- After evaluating all the options, it is clear that **Carbamates** are the least persistent insecticide among the given choices. They degrade more readily than Aldrin, Dieldrin, and BHC.

### Final Answer:
The least persistent insecticide is **Carbamates**.

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