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: Formerly known as Sky Dome, Rogers Centre is home to what American League baseball team, the only MLB team located outside the United States?

Answer: american league


Question: Which horse won the 2009 Epsom Derby?

Answer: 2009 epsom derby


Question: Which of these tracks was a hit for Duane Eddy?

Answer:
duane eddy