Green muffler is used against which type of pollution?

Options

A. air
B. soil
C. water
D. noise

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks about the type of pollution that a "green muffler" is used to combat.

2. **Identifying the Options:** The options provided are air, soil, water, and noise pollution.

3. **Defining Green Muffler:** A green muffler refers to a method or strategy that involves planting trees or vegetation in a specific arrangement to mitigate pollution.

4. **Analyzing the Purpose of Green Muffler:** The primary function of a green muffler is to reduce noise pollution. It is particularly effective in areas with high levels of noise, such as near highways or industrial zones.

5. **Mechanism of Action:** The dense planting of trees (4 to 6 plants in a row) creates a barrier that absorbs and filters out excessive noise, thereby reducing its impact on nearby communities.

6. **Conclusion:** Based on the analysis, the green muffler is used to reduce noise pollution.

**Final Answer:** The green muffler is used against noise pollution.

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