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: Which instrument was Benny Goodman famous for playing?

Answer: benny goodman


Question: Which of these was the title of Bobby Darin's first million selling single?

Answer: bobby darin


Question: Which city was the site of the dervish rebellion and the death of the British General Gordon in 1885?

Answer:
charles george gordon