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

Ex Input:
The most northerly part of mainland Australia is in which state?

Ex Output:
australia


Ex Input:
Of all the actors who played Doctor Who in the TV series of the same name, who appeared in the most episodes?

Ex Output:
doctor who


Ex Input:
Which famous book features the character of Bob Cratchit?

Ex Output:

bob cratchit