What are the two main causes of acidi will mark you as brainlinest for correct

Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain. so in that case i believe that the answer is D natural and resource distribution 

Answerweathering;