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

Q: What is the smallest country in Central America Costa Rica, Venezuela or El Salvador?

A: central america
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Q: What American swimmer won eight gold medals at the 2008 Olympics?

A: 2008 summer olympics
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Q: Which capital city is served by Arlanda Airport?

A:
stockholm arlanda airport
****