Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.

Q: What nickname is given to the Australian Association Football International team?

A: australia
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Q: Which Best Picture nominated movie tells the story of US soldier, 'Chris' Kyle?

A: chris kyle
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Q: The Cagayan River is the largest river in which country?

A:
cagayan river
****