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 actress played Arwen in the trilogy of films?

SOLUTION: arwen

PROBLEM: The rivers Axe, Brue, Cary, Parrett, eta, are in which English county?

SOLUTION: castle cary

PROBLEM: Demi Moore shaved her head for the title role in which 1997 film?

SOLUTION:
demi moore