Task: Question Answering
Input (English): Burning fossil fuels produces sulfur dioxide (SO2) and nitrogen oxide (NO). These compounds react with water vapor to produce acid rain. What is the most likely effect of acid rain on the environment where it falls?  
 (A) The plants and animals in lakes and ponds will be harmed. (B) The soil in the area will become more alkaline. (C) The thickness of the ozone layer will decrease. (D) Levels of air pollution will increase.
Output (English): A