Task: Question Answering
Input (English): Fossils of clam shells were found in the Appalachian Mountains. Which of these statements best explains why the clam shells were found in the Appalachian Mountains?  
 (A) The mountain range was once under water. (B) Birds flying overhead dropped the clam shells. (C) Animals released the clam shells in their waste. (D) The clams lived on land before moving to water.
Output (English): A