Which one of the following gaseous pollutants is carcinogenic?

Options

A. Oxides of sulphur
B. Oxides of nitrogen
C. Arsenic
D. Oxides of carbon

Answer

To determine which gaseous pollutant is carcinogenic, we will analyze the options provided and identify the one that is known to cause cancer.

### Step-by-Step Solution:

1. **Understanding Carcinogenicity**:
- Carcinogenic means the ability of a substance to cause cancer. We need to identify which gaseous pollutant has this property.

2. **Identifying Common Gaseous Pollutants**:
- Common gaseous pollutants include oxides of sulfur (SOx), nitrogen (NOx), carbon (CO, CO2), and metals like arsenic when in gaseous form.

3. **Analyzing Each Option**:
- **Oxides of Sulfur (SOx)**: These are primarily associated with respiratory problems but are not classified as carcinogenic.
- **Oxides of Nitrogen (NOx)**: Similar to sulfur oxides, these contribute to respiratory issues and smog but are not directly linked to cancer.
- **Carbon Monoxide (CO)**: This gas is toxic and can cause serious health issues but is not classified as a carcinogen.
- **Arsenic**: This is a metalloid that can be found in gaseous form (as arsenic trioxide) and is known to be carcinogenic, particularly linked to lung cancer and skin cancer.

4. **Conclusion**:
- Among the options, arsenic is recognized as a carcinogenic pollutant. Therefore, the correct answer is arsenic.

### Final Answer:
The gaseous pollutant that is carcinogenic is **Arsenic**.

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