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: Chep Lap Kok airport is located where?

Answer: hong kong international airport


Question: Which Afro American super model, TV personality and singer hosts the TV show, America's Next Top Model and also has her own daytime TV chat show?

Answer: america's next top model


Question: What is the name of Beethoven's only opera?

Answer:
ludwig van beethoven