The major source of CO pollution is

Options

A. vehicular exhaust
B. industrial processes
C. forest fires
D. deforestation.

Answer

**Step-by-Step Solution:**

1. **Understanding Carbon Monoxide (CO):**
- Carbon monoxide is a colorless, odorless gas that can be harmful to human health when inhaled. It is produced during the incomplete combustion of carbon-containing fuels.

2. **Identifying Sources of CO:**
- The question asks for the major source of carbon monoxide pollution. We need to analyze the options provided:
- A. Vehicular exhaust
- B. Industrial processes
- C. Forest fire
- D. Deforestation

3. **Analyzing Each Option:**
- **A. Vehicular exhaust:**
- Vehicles that burn fossil fuels (like gasoline and diesel) release carbon monoxide due to incomplete combustion. This is a significant contributor to outdoor air pollution.
- **B. Industrial processes:**
- While industries do contribute to air pollution, they are more commonly associated with the release of carbon dioxide and sulfur oxides rather than carbon monoxide.
- **C. Forest fire:**
- Forest fires primarily release carbon dioxide, nitrogen dioxide, methane, and ozone, but not as significant a source of carbon monoxide compared to vehicular exhaust.
- **D. Deforestation:**
- Deforestation leads to increased carbon dioxide levels as trees, which act as carbon sinks, are removed. It does not significantly contribute to carbon monoxide pollution.

4. **Conclusion:**
- After evaluating all the options, the major source of carbon monoxide pollution is clearly **A. Vehicular exhaust**. This is due to the high number of vehicles on the road and their reliance on fossil fuels, which leads to incomplete combustion and the release of CO.

**Final Answer:** The major source of carbon monoxide pollution is A. Vehicular exhaust.

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