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

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

Which popular Doctor Who villains, it was revealed in 2011, are to be given 'a rest' by scriptwriters?
doctor who

In which Irish county is the extensive area of limestone pavement known as The Burren?

the burren