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: 'Arthur Clennam', 'Jeremiah Flintwinch', and 'Edward Sparkler' are all characters in which Dickens' novel?

Answer: arthur clennam

Question: Auld Reekie is the nickname for which Scottish city?

Answer: auld reekie

Question: Born in Argentina in 1942, which pianist and conductor has been has been music director of the Berlin State Opera since 1992, and was music director of the Chicago Symphony Orchestra from 1991 to 2006?

Answer:
chicago symphony orchestra