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 boxer was nicknames `The Brown Bomber`?

Answer: boxing


Question: Against which country did Britain fight 'The Cod Wars'?

Answer: cod wars


Question: The BWV catalogue lists the works of which 17/18th century composer?

Answer:
bach-werke-verzeichnis