Answer: Option (a) is the correct answer.
Step-by-step explanation:
Nitrogen oxide and sulfur dioxide released into the air results in the formation of acid rain.
This is because both nitrogen oxide and sulfur oxide are able to rise high into the atmosphere. These oxides mix and react with water, oxygen and other chemicals and thus it forms more acidic pollutants which are known as acid.
Thus, we can conclude that nitrogen oxides and sulfur oxides make acid rain.