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: Princess Estelle, Duchess of Ostergotland, granddaughter to King Carl XVI Gustaf, became 2nd in line to what nation's throne when born in 2012?

Answer: carl xvi gustaf of sweden


Question: The Bob Dylan songs 'Desolation Row', 'Tombstone Blues' and 'Like A Rolling Stone' featured on which album?

Answer: tombstone blues


Question: Jacob Black, Edward Cullen, and Bella Swan are characters in what fictional book series?

Answer:
bella swan