Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
--------
Question: Who wrote the novel 'Brideshead Revisited'?

Answer: brideshead revisited


Question: What are Proxima Centauri, Sirius A, Pollux, Arcturus and Betelgeuse?

Answer: arcturus


Question: In which country is Cotopaxi, the highest active volcano in the world?

Answer:
cotopaxi