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: Cilantro is the leaf of which herb?

Answer: cilantro


Question: Established in 1919, which is the world's oldest surviving airline?

Answer: airline


Question: Who provided the voice of the genie in the 1992 animated film Aladdin?

Answer:
aladdin