Which of the following is used as a weedicide?

Options

A. Malathion
B. Disyston
C. Dalapon
D. Gammaxane

Explanation

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks which of the given options is used as a weedicide. A weedicide is a chemical that is specifically used to kill unwanted plants, known as weeds, in agricultural fields.

2. **Identifying the Options**: The options provided are Melathion, Dicestone, Gammaxine, and Dallapon. We need to analyze each one to determine which is a weedicide.

3. **Analyzing Melathion**: Melathion is a chemical that is primarily used as an insecticide. It targets and kills insects, not weeds. Therefore, Melathion is not a weedicide.

4. **Analyzing Dicestone**: Dicestone is also used as an insecticide, particularly against caterpillars. Similar to Melathion, it does not serve the purpose of killing weeds. Hence, Dicestone is not a weedicide.

5. **Analyzing Gammaxine**: Gammaxine is another insecticide that is effective against various insects such as beetles, caterpillars, and worms. Like the previous two, it is not used to control weeds, so Gammaxine is not a weedicide.

6. **Analyzing Dallapon**: Dallapon is a chemical specifically designed to kill unwanted weeds and plants in crop fields. It is classified as a weedicide, making it the correct answer to the question.

7. **Conclusion**: After analyzing all the options, the correct answer is Dallapon, as it is the only chemical listed that is used as a weedicide.

### Final Answer: Dallapon

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