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 is the name of the US electric car manufacturer, founded in 2003, whose cars include the Model S and the Model X?

Answer: tesla model s


Question: What nationality was Che Guevara?

Answer: che guevara


Question: In which country does the Amazon River rise?

Answer:
amazon river