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: What name was given to the 1950-60s mainstream country music style of artists including Patsy Cline, Tammy Wynette, Jim Reeves, and Charlie Rich?

Answer: charlie rich


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 wrote the WW11 novel 'The Cruel Sea'?

Answer:
the cruel sea