Which one of the following gases is considered an atmospheric pollutant?

Explanation

Sulphur dioxide (SO₂) and ozone are considered atmospheric pollutants. They can affect both health and the environment. Short-term exposure to sulphur dioxide (SO₂) can harm the human respiratory system and cause breathing difficulties. The largest source of sulphur dioxide (SO₂) in the atmosphere is the burning of fossil fuels in power plants and other industrial activities. Ground-level ozone, or tropospheric ozone, is a secondary pollutant. It is formed when nitrogen oxides (NOx) and volatile organic compounds (VOCs) released from vehicles, industries, and power plants react in the presence of sunlight.