Which of the following is not a gaseous pollutant in the atmosphere?

Atmospheric aerosols are tiny solid or liquid particles suspended in air, making them particulate rather than a gaseous pollutant.

They form particulate matter such as dust, soot and smoke instead of a gas.

Tropospheric ozone is a genuine gaseous pollutant formed near the ground.

Sulphur dioxide is a gaseous pollutant released mainly from burning coal.

Nitrogen dioxide is another gaseous pollutant from vehicles and combustion.

Aerosols are measured as particulate matter and can travel deep into the lungs.