Task: Question Answering
Input (English): A student stands outside on a cold winter day. His hands become cold and he rubs them together to make them warmer. Which statement explains why rubbing his hands together makes them warmer?  
 (A) This action produces thermal energy through friction. (B) This action conducts thermal energy away from the body. (C) This action captures thermal energy from the environment. (D) This action reduces the amount of thermal energy transferred to the air.
Output (English): A