Acid rains are produced by

• A.  excess \[N{{O}_{2}}\] and \[S{{O}_{2}}\] from burning fossil fuels
• B.  excess production of \[N{{H}_{3}}\] by industry and coal gas
• C.  excess release of carbon monoxide by incomplete combustion
• D.  excess formation of \[C{{O}_{2}}\] by combustion and animal respiration. (1988, 89)