Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.

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

A: american league
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Q: Besides the Caucasus, what mountain range forms the border of Europe and Asia?

A: asia
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Q: Who has written a series of novels, entitled The Dark Tower, of which the first, in 1982, was entitled, The Gunslinger?

A:
the dark tower
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