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: Who wrote the novel 'Brideshead Revisited'?

Answer: brideshead revisited


Question: Which British TV star and disc jockey said `It`s not affected my work - how healthy do you have to be to play Da Do Ron Ron` in 1992 after confirming he had AIDS?

Answer: hiv/aids


Question: Which rank of the peerage is directly below a duke?

Answer:
duke