instruction:
Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
question:
The plays 'The Barber of Seville' and 'Marriage of Figaro' were written by whom?
answer:
the marriage of figaro

question:
The most northerly part of mainland Australia is in which state?
answer:
australia

question:
Nick Carter first entered the pop charts as a member of which boy band?
answer:
boy band