Source(s) of nitrogen oxides is

Options

A. Industrial combustion
B. Forest fibre, automobile
C. Power-generating stations
D. All

Answer

**Step-by-Step Solution:**

1. **Understanding Nitrogen Oxides**: Nitrogen oxides (NOx) are a group of gases that are composed of nitrogen and oxygen. They are primarily produced from combustion processes.

2. **Identifying Sources**: The question asks for the sources of nitrogen oxides. Common sources include:
- **Industrial Combustion**: Factories and industrial plants burn fossil fuels for energy, which releases nitrogen oxides into the atmosphere.
- **Forest Fires**: Natural events like forest fires also contribute to the release of nitrogen oxides as organic material burns.
- **Automobile Emissions**: Cars and other vehicles burn gasoline or diesel, which leads to the production of nitrogen oxides as a byproduct of combustion.
- **Power Generating Stations**: Power plants that burn fossil fuels to generate electricity also emit nitrogen oxides.

3. **Conclusion**: Based on the sources identified, the correct answer to the question is that nitrogen oxides come from industrial combustion, forest fires, automobile emissions, and power generating stations.

**Final Answer**: The sources of nitrogen oxides include:
- Industrial combustion
- Forest fires
- Automobile emissions
- Power generating stations

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