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

Q: On November 22, 1986, which boxer became the youngest WBC Heavyweight champion, at age 20 years, 4 months, when he scored a TKO over Trevor Berbick in the second round?

A: boxing
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Q: Who wrote the 1939 book The Big Sleep?

A: the big sleep
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Q: Buenos Aires is the capital city of which country?

A:
buenos aires
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