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

Q: What currency is used on Christmas Island?

A: christmas island
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Q: What horse won the 2009 Grand National?

A: 2009 grand national
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Q: What is the name of Captain Jack Aubrey's ship in the 2003 film 'Master and Commander: the Far Side of the World'?

A:
jack aubrey
****