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 stars in the TV series Californication?

SOLUTION: californication

PROBLEM: In which wars did the battles of Towton and Barnet take place?

SOLUTION: battle of barnet

PROBLEM: With which instrument was Charlie Christian associated?

SOLUTION:
charlie