Which one of the following is a herbicide?

Options

A. Organochlorines
B. Organophosphates
C. Carbamates
D. Sodium arsenite

Answer

To determine which of the following options is a herbicide, we need to understand what a herbicide is and differentiate it from other types of pesticides.

### Step-by-Step Solution:

1. **Define Herbicides**:
- Herbicides are chemicals used to control or kill unwanted plants, commonly known as weeds. They are specifically designed to target plant growth without harming the crops.

2. **Identify the Options**:
- The options given are:
1. Organochlorine
2. Organophosphate
3. Carbamates
4. Sodium Arsenide

3. **Classify the Options**:
- **Organochlorines**, **Organophosphates**, and **Carbamates** are primarily classified as insecticides. They are used to control insect pests that can damage crops.
- **Sodium Arsenide** is a compound that has been used as a herbicide, although it is less preferred today due to its toxicity to mammals.

4. **Select the Correct Answer**:
- Among the options, Sodium Arsenide is identified as a herbicide, even though it is not commonly used now due to safety concerns. The other three options are insecticides.

5. **Conclusion**:
- Therefore, the correct answer to the question "Which one of the following is a herbicide?" is **Sodium Arsenide**.

### Final Answer:
**Sodium Arsenide** is the herbicide among the given options.

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