TASK DEFINITION: Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
PROBLEM: Aaron Copeland wrote a ballet about which American folk hero?

SOLUTION: aaron copeland

PROBLEM: What was the first British credit card?

SOLUTION: credit card

PROBLEM: Who became Roman emperor after the murder of Caligula, and, after the death of his wife, married his niece Agrippina, who poisoned him?

SOLUTION:
caligula