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: What was the first Apollo mission to leave Earth orbit and orbit the moon, in 1968?

Answer: apollo


Question: Which Irish boxer was nicknamed the Clones Cyclone?

Answer: boxing


Question: Who took Angel of Mine to the top of the Billboard charts for 4 weeks in 1999?

Answer:
angel of mine