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: Betty Driver played which role in Coronation Street?

Answer: betty driver


Question: Mr Barkis, Edward Murdstone and Tommy Traddles are all characters in which Charles Dickens novel?

Answer: charles dickens


Question: As at 2004, which actor is the only member of the original Coronation Street cast who is still in the show?

Answer:
coronation street