Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
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Question: In 2013 Yahoo purchased which pictures and video microblogging website business that was founded in 2007 in New York City by David Karp?

Answer: yahoo!


Question: Who married the woman who was to become Queen Beatrix of the Netherlands, on 10 March 1966?

Answer: beatrix


Question: Which river is spanned by the Clifton Suspension Bridge?

Answer:
clifton suspension bridge