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

Q: In 2013 Yahoo purchased which pictures and video microblogging website business that was founded in 2007 in New York City by David Karp?

A: yahoo!
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Q: The 2002 Winter Olympics were held in which city?

A: 2002 winter olympics
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Q: The rivers Gowy, Goyt and Bollin are tributaries of which larger river?

A:
river goyt
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