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

[Q]: Name Alfred Hitchcock's first sound film as director?
[A]: alfred hitchcock

[Q]: In which city were the 2002 Winter Olympic Games held?
[A]: 2002 winter olympics

[Q]: 'Atlas', 'Mimas' and 'Calypso' are three of the satellites of which planet?
[A]:
calypso