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 Best Picture nominated movie tells the story of US soldier, 'Chris' Kyle?

Answer: chris kyle


Question: Which film was based on the story The Sentinel by Arthur C Clarke?

Answer: arthur c. clarke


Question: What American TV serial, first broadcast between April 1990 and June 1991, followed an investigation headed by Special Agent Dale Cooper?

Answer:
dale cooper