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 horse won the 2008 Grand National?

SOLUTION: 2008 grand national

PROBLEM: The wine-producing region of Hunter Valley is in which Australian state?

SOLUTION: australia

PROBLEM: Which unsuccessful Apollo program was launched in April 1970?

SOLUTION:
apollo program