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

Q: What is the smallest country in Central America Costa Rica, Venezuela or El Salvador?

A: central america
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Q: Chep Lap Kok airport is located where?

A: hong kong international airport
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Q: Which famous actor is well known for his voice over work, including the This is CNN tag and the voice of Darth Vader in the Star Wars film franchise?

A:
darth vader
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