TASK DEFINITION: Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
PROBLEM: Who was the CBS News anchor-man known as 'the man Americans most trust'?

SOLUTION: news presenter

PROBLEM: Which English king was married to Eleanor of Castile?

SOLUTION: eleanor of castile

PROBLEM: In the Old Testament, who is the sister of Moses and Aaron?

SOLUTION:
aaron