Which of these components present in the air is a pollutant?

Options

A. Oxygen
B. Water vapour
C. Carbon dioxide
D. Sulphur dioxide

Answer

To determine which component present in the air is a pollutant, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Composition of Air**:
- Air is a mixture of various gases. The major components include nitrogen (N2), oxygen (O2), carbon dioxide (CO2), and trace gases.

2. **Identify Common Components**:
- The common components of air include:
- Nitrogen (N2) - approximately 78%
- Oxygen (O2) - approximately 21%
- Carbon Dioxide (CO2) - approximately 0.03%
- Water vapor and other trace gases.

3. **Determine Which Components Are Pollutants**:
- Pollutants are substances that cause harm to the environment and living organisms.
- While nitrogen and oxygen are essential for life and not considered pollutants, carbon dioxide is a natural component of air and is necessary for photosynthesis in plants, although in high concentrations it can contribute to global warming.
- Sulfur dioxide (SO2) is a significant pollutant that can cause air pollution and respiratory problems.

4. **Conclusion**:
- Among the components mentioned, sulfur dioxide (SO2) is identified as a pollutant.

### Final Answer:
The component present in the air that is a pollutant is **sulfur dioxide (SO2)**.

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