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 term "Green Muffler":**
- The term "green muffler" refers to the use of vegetation, particularly trees and plants, to mitigate environmental issues.

2. **Identifying the type of pollution:**
- The question asks about the type of pollution that green mufflers are used against.

3. **Analyzing the options:**
- The options provided are:
- Air
- Swale
- Water
- Noise

4. **Evaluating each option:**
- **Air Pollution:** Green mufflers do help in improving air quality, but they are primarily known for their role in noise reduction.
- **Swale:** This term refers to a shallow channel designed to manage water runoff, not a type of pollution.
- **Water Pollution:** Green mufflers do not directly address water pollution.
- **Noise Pollution:** Green mufflers are specifically used to reduce noise pollution by absorbing sound, especially in noisy urban areas.

5. **Conclusion:**
- Based on the analysis, the correct answer is that green mufflers are used against **Noise Pollution**.

**Final Answer:** Green muffler is used against Noise Pollution.

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