Task: Question Answering
Input (English): The metal lid on a glass jar is hard to open, so it is held under warm, running water. What causes the jar to open easily after it was held under the water?  
 (A) The water increased the pressure under the lid. (B) The jar shrunk with the warm water. (C) The water acted as a lubricant between the glass and the metal. (D) The metal lid expanded under warm water.
Output (English): D