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

Q: 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?

A: hiv/aids
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Q: What is the main river of Brazil?

A: brazil
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Q: What number Apollo was the last one to land a man on the moon?

A:
moon
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