Acid rain is caused by the pollution of environment by

Correct Option (D):

Acid rain is primarily caused by the atmospheric pollution from sulphur dioxide (SO₂) and oxides of nitrogen (NOₓ), which include nitrous oxide (N₂O). These gases are released into the atmosphere mainly from the combustion of fossil fuels in power plants, industrial processes, and vehicular emissions. Once in the atmosphere, SO₂ and NOₓ react with water vapour, oxygen, and other chemicals to form sulphuric acid (H₂SO₄) and nitric acid (HNO₃), respectively. These strong acids then fall to the Earth's surface as precipitation, lowering its pH and causing environmental damage to forests, aquatic ecosystems, soil, and man-made structures.

Incorrect Options:

Carbon dioxide (CO₂) is a major greenhouse gas contributing to global warming and climate change. While it dissolves in water to form carbonic acid (H₂CO₃), a weak acid, it does not cause acid rain in the damaging sense associated with H₂SO₄ and HNO₃. Nitrogen (N₂) is the most abundant gas in the atmosphere and is largely inert under normal conditions, not contributing to acid rain.

Carbon monoxide (CO) is a toxic air pollutant resulting from incomplete combustion, and carbon dioxide (CO₂) is a greenhouse gas. Neither of these gases is a primary cause of acid rain.

Ozone (O₃) in the troposphere is a secondary pollutant that contributes to photochemical smog and is harmful to respiratory systems. Carbon dioxide (CO₂) is a greenhouse gas. Neither ozone nor carbon dioxide are direct precursors to the strong acids that cause acid rain.