The answer is (A) burning fossils fuels releases excess amounts of CO2 ( Carbon dioxide) which reacts with H2O in the atmosphere.
CO2 + H2O -> H2CO3
H2CO3 is known as carbonic acid.
Carbonic acid contributes to problems such as ocean acidification and can dissolve limestone ( CaCO3) sculptures.
Shown by this reaction H2CO3 + CaCO3 -> Ca(HCO3)2 producing Calcium Hydrogen Carbonate.
There are also different causes of acid rain such as Sulfur Dioxide (SO2) and Nitrogen Oxide (NO) which can cause respiratory problems.