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: Which evolutionary biologist wrote The Ancestor's Tale in 2004?

Answer: the ancestor's tale

Question: In what story of Arthur C. Clarke do Tibetan monks seek to list all the names of God as they believe He will bring the Universe to an end once this is done?

Answer: arthur c. clarke

Question: The Amazon river rises in which country?

Answer:
amazon river