Which of the followin acts as a pollutant ?

Options

A. CO
B. `SO_(2)`
C. `CO_(2)`
D. `O_(2)`

Answer

**Step-by-Step Solution:**

1. **Define Pollutant:**
A pollutant is defined as a substance or energy introduced into the environment that has undesired effects or adversely affects the usefulness of a resource. Pollutants can harm air, water, and soil, and can negatively impact human health and ecosystems.

2. **Identify Common Pollutants:**
Common examples of pollutants include gases like carbon monoxide (CO) and sulfur dioxide (SO2). These substances are known for their harmful effects on the environment and human health.

3. **Discuss Carbon Monoxide (CO):**
- Carbon monoxide is a colorless and tasteless gas produced from the incomplete combustion of carbon-containing fuels such as oil and coal.
- It is a significant air pollutant that can lead to health issues in humans and is also a greenhouse gas contributing to climate change and global warming.

4. **Discuss Sulfur Dioxide (SO2):**
- Sulfur dioxide is another harmful pollutant that can combine with air and water to form sulfuric acid.
- This process contributes to acid rain, which can lead to environmental issues such as deforestation and damage to aquatic ecosystems.

5. **Conclusion:**
Based on the definitions and examples discussed, both carbon monoxide (CO) and sulfur dioxide (SO2) act as pollutants. Therefore, the correct answer to the question is that both of these substances are pollutants.

**Final Answer:**
Carbon monoxide (CO) and sulfur dioxide (SO2) act as pollutants.

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