Most harmful pollutant is

Options

A. `CO_(2)`
B. `SO_(2)`
C. `NO_2`
D. `CH_4`

Answer

**Step-by-Step Solution:**

1. **Identify the Context of the Question**: The question asks for the most harmful pollutant. To answer this, we need to consider various pollutants and their effects on health and the environment.

2. **List Common Pollutants**: Some common pollutants include sulfur dioxide (SO₂), nitrogen oxides (NOx), carbon monoxide (CO), particulate matter (PM), and ozone (O₃).

3. **Evaluate the Effects of Each Pollutant**:
- **Sulfur Dioxide (SO₂)**: Can cause acid rain, respiratory problems, and damage to vegetation.
- **Nitrogen Oxides (NOx)**: Contributes to smog formation, respiratory issues, and can lead to the formation of ground-level ozone.
- **Carbon Monoxide (CO)**: A colorless, odorless gas that can cause harmful health effects by reducing the blood's ability to carry oxygen.
- **Particulate Matter (PM)**: Can penetrate deep into the lungs and even enter the bloodstream, causing serious health issues.
- **Ozone (O₃)**: At ground level, it can cause respiratory problems and is harmful to plants.

4. **Determine the Most Harmful Pollutant**: Based on the effects listed, sulfur dioxide is particularly harmful as it can lead to severe environmental damage (acid rain) and significant health issues (asthma, bronchitis).

5. **Conclude the Answer**: Therefore, the most harmful pollutant is sulfur dioxide (SO₂).

**Final Answer**: Sulfur Dioxide (SO₂)

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