Burning fossil fuels such as coal and gasoline
We know that burning fossil fuels, such as coal and gasoline, is a significant human activity that contributes to the formation of acid rain.
When fossil fuels are burned, they release pollutants into the atmosphere, including sulfur dioxide (SO2) and nitrogen oxides (NOx).
These pollutants can react with water, oxygen, and other chemicals in the atmosphere to form sulfuric acid (H2SO4) and nitric acid (HNO3), which are major components of acid rain.
Therefore the correct answer is
Burning fossil fuels such as coal and gasoline