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

Answer: tombstone blues


Question: What is the second largest of the Balearic Islands ?

Answer: balearic islands


Question: Aragon and Castile joined to form which country?

Answer:
aragon