Which one of the following pollutants is responsible for acid rain formation?

Sulphur dioxide reacts with water vapour to form sulphuric acid, a main cause of acid rain.

Methane is a greenhouse gas but does not form acids in the atmosphere.

Benzene is a toxic volatile organic compound, not an acid-rain precursor.

Carbon monoxide is a poisonous gas but does not produce acid rain.

Nitrogen oxides, alongside sulphur dioxide, also contribute to acid rain.

Acid rain damages soils, forests, lakes and limestone buildings.