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: Come Clean was the debut album by which 2000s band?

Answer: come clean


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

Answer: arthur c. clarke


Question: Durum, Spelt, and Einkorn are all types of what?

Answer:
einkorn wheat