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

Who was Prime Minister of Australia at the outbreak of World War I?
australia

In which constellation is the star Deneb?
deneb

Bechamel, Espagnole, Veloute, Hollandaise, Tomate are the five 'mother (what)' of classical French cuisine?

bechamel sauce