TASK DEFINITION: Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
PROBLEM: Which English king was married to Eleanor of Castile?

SOLUTION: eleanor of castile

PROBLEM: Which jockey rode Red Alligator to victory in the 1968 Grand National?

SOLUTION: red alligator

PROBLEM: In which class did boxer Amir Khan win the Silver medal at the 2004 Olympics?

SOLUTION:
amir khan