2,4-dichlorophenoxy acetic acid is used as a

Options

A. fungicide
B. insecticide
C. herbicide
D. moth repellant

Explanation

**Step-by-Step Solution:**

1. **Identify the Compound**: The compound in question is 2,4-Dichlorophenoxyacetic acid, commonly referred to as 2,4-D. Its chemical formula is C8H6Cl2O3.

2. **Determine the Classification**: To understand the use of 2,4-D, we need to classify it. The options provided are fungicide, insecticide, herbicide, and moth repellent.

3. **Research the Function**: 2,4-D is known to be an organic compound that is primarily used in agriculture. It is important to determine its specific function in this context.

4. **Define Herbicide**: A herbicide is a type of pesticide that is specifically designed to kill unwanted plants, commonly referred to as weeds. The term "herb" refers to plants, while "cide" means to kill.

5. **Identify Target Plants**: 2,4-D is particularly effective against broadleaf weeds. These are unwanted plants that compete with crops for nutrients, water, and light.

6. **Conclusion**: Based on the classification and function of 2,4-D, we conclude that it is used as a herbicide. This means it is used to control and eliminate unwanted broadleaf weeds in various agricultural settings.

**Final Answer**: 2,4-Dichlorophenoxyacetic acid is used as a herbicide.

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