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

Q: Chris Martin is the lead singer with which band who had several hits in the 2000s?

A: chris martin
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Q: In which city will the 2014 Tour de France begin?

A: 2014 tour de france
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Q: Who was president of the USA during the American Civil War?

A:
american civil war
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