Final answer:
Acid rain is primarily caused by emissions of sulfur dioxide and nitrogen oxides resulting from the combustion of fossil fuels, leading to the formation of sulfuric and nitric acids. The correct option is 2.
Step-by-step explanation:
The primary source of acid rain is due to emissions of sulfur dioxide (SO₂) and nitrogen oxides (NOₓ) from the combustion of fossil fuels. When these gases react in the atmosphere with water, oxygen, and other chemicals, they form various acidic compounds, leading to a mild solution of sulfuric acid and nitric acid.
It's not ozone, carbon monoxide, or carbon dioxide that are the principal causes for acid rain, but sulfur oxides and nitrogen oxides that play a major role in its formation.
Hence, Option 2 is correct.