Consider the following statements regarding air pollution.I. Use of mass transit system reduces air pollution. II. Fuels such as CNG should be encouraged to reduce air pollution. III. Burning crackers reduces the co, content of air.
Among the given statements,

Options

A. only statement I is true
B. only statement III is true
C. statement I and II are true
D. statement II and III are true

Answer

To determine which statements regarding air pollution are correct, let's analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement I: Use of mass transit system reduces air pollution.**
- **Analysis:** The use of a mass transit system, such as buses or trains, reduces the number of individual vehicles on the road. Fewer vehicles mean less fuel consumption and lower emissions of pollutants, including carbon monoxide and other harmful gases. Therefore, this statement is **correct**.

2. **Statement II: Fuels such as CNG should be encouraged to reduce air pollution.**
- **Analysis:** Compressed Natural Gas (CNG) is a cleaner alternative to traditional fossil fuels like petrol and diesel. It produces fewer pollutants and greenhouse gases when burned. Encouraging the use of CNG can significantly help in reducing air pollution. Thus, this statement is also **correct**.

3. **Statement III: Burning crackers reduces the carbon monoxide content of air.**
- **Analysis:** Burning crackers (fireworks) actually increases air pollution, including the emission of carbon monoxide and other harmful substances. Therefore, this statement is **incorrect**.

### Conclusion:
- **Correct Statements:** I and II are correct.
- **Incorrect Statement:** III is incorrect.

### Final Answer:
Among the given statements, I and II are correct, while III is incorrect.

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