Which of the following gas does not create air pollution ?

Options

A. Sulphuric oxide
B. Carbon monoxide
C. CNG
D. None of these

Explanation

To determine which gas does not create air pollution, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Identify the Gases**: We need to look at the options given in the question. The gases mentioned are sulfur dioxide (SO2), carbon monoxide (CO), and compressed natural gas (CNG).

2. **Analyze Sulfur Dioxide (SO2)**:
- Sulfur dioxide is a significant contributor to air pollution. It is primarily produced from industrial processes and the burning of fossil fuels.
- **Conclusion**: SO2 does create air pollution.

3. **Analyze Carbon Monoxide (CO)**:
- Carbon monoxide is another harmful gas that contributes to air pollution. It is produced from incomplete combustion of carbon-containing fuels, such as in vehicles and industrial processes.
- **Conclusion**: CO does create air pollution.

4. **Analyze Compressed Natural Gas (CNG)**:
- Compressed natural gas is a cleaner alternative to traditional fuels like petrol and diesel. It burns more efficiently and produces fewer pollutants, including lower emissions of sulfur dioxide and carbon dioxide.
- **Conclusion**: CNG is considered eco-friendly and does not contribute to air pollution.

5. **Final Decision**: Based on the analysis, the gas that does not create air pollution is **Compressed Natural Gas (CNG)**.

### Answer:
The gas that does not create air pollution is **CNG (Compressed Natural Gas)**.

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