Which industry is the main source of gaseous pollutants like sulphur dioxide and nitrogen dioxide in Agra?

Explanation

**Step-by-Step Solution:**

1. **Understanding Air Pollution**: Begin by defining air pollution. It refers to the contamination of the air due to harmful substances, which can lead to a decline in air quality.

2. **Identifying Gaseous Pollutants**: Recognize the specific gaseous pollutants mentioned in the question, which are sulfur dioxide (SO2) and nitrogen dioxide (NO2). These gases are known to contribute to air pollution and can cause respiratory diseases.

3. **Finding the Source**: Investigate which industries are prominent in Agra and their contributions to air pollution.

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