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 of the given gaseous pollutants is carcinogenic, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Carcinogenic Pollutants**:
- Carcinogenic pollutants are substances that have the potential to cause cancer in living tissues.

2. **Evaluating Option 1: Oxides of Sulfur**:
- Oxides of sulfur, such as sulfur dioxide (SO2) and sulfur trioxide (SO3), are known to be harmful to the environment and can cause respiratory problems. However, they are not classified as carcinogenic.
- **Conclusion**: Option 1 is not carcinogenic.

3. **Evaluating Option 2: Oxides of Nitrogen**:
- Oxides of nitrogen, including nitrogen dioxide (NO2) and nitric oxide (NO), are also pollutants that can affect air quality and lead to respiratory issues. Similar to sulfur oxides, they are not known to cause cancer.
- **Conclusion**: Option 2 is not carcinogenic.

4. **Evaluating Option 3: Arsenic**:
- Arsenic is a well-known carcinogen. It can be found in contaminated drinking water and has been linked to various types of cancer, including bladder cancer and skin cancer.
- **Conclusion**: Option 3 is carcinogenic.

5. **Evaluating Option 4: Oxides of Carbon**:
- Oxides of carbon, such as carbon monoxide (CO) and carbon dioxide (CO2), are significant environmental pollutants. However, they are not classified as carcinogenic substances.
- **Conclusion**: Option 4 is not carcinogenic.

### Final Answer:
Based on the analysis, the gaseous pollutant that is carcinogenic is **Option 3: Arsenic**.

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