instruction:
Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
question:
Which Best Picture nominated movie tells the story of US soldier, 'Chris' Kyle?
answer:
chris kyle


question:
Trujillo and Chiclayo are cities in which country in the Americas?
answer:
chiclayo


question:
Who wrote the book Catch-22?
answer:

catch-22