2,4 - dichlorophenoxyacetic acid is used to eliminate ..... Weeds from a .... Crop field .

Options

A. monocotydonous , dicot , dicot
B. dicotyledonous monocot
C. biennial , annual
D. biennial , perennial

Answer

To solve the question regarding the use of 2,4-dichlorophenoxyacetic acid (commonly known as 2,4-D) in agriculture, we can break it down into a few steps:

### Step-by-Step Solution:

1. **Understanding 2,4-Dichlorophenoxyacetic Acid**:
- 2,4-D is a synthetic herbicide that belongs to the class of chemicals known as auxins. Auxins are plant hormones that regulate growth and development in plants.

2. **Function of 2,4-D**:
- The primary function of 2,4-D is to control and eliminate certain types of weeds, particularly broadleaf weeds (dicots), while having minimal effect on grasses (monocots).

3. **Identifying the Target Weeds**:
- Since 2,4-D is effective against dicotyledonous weeds, it is used to eliminate these types of weeds from crop fields.

4. **Identifying the Crop Field**:
- The crop fields where 2,4-D is commonly used are typically monocot crops, such as cereals (e.g., wheat, rice, corn), which are less affected by this herbicide.

5. **Conclusion**:
- Therefore, we can conclude that 2,4-dichlorophenoxyacetic acid is used to eliminate dicot weeds from a monocot crop field.

### Final Answer:
2,4-Dichlorophenoxyacetic acid is used to eliminate dicot weeds from a monocot crop field.

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