instruction:
Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
question:
Which two brothers had hits with Cathy's Clown and Wake Up Little Susie?
answer:
cathy's clown


question:
In which war did the Sack of Badajoz takeplace?
answer:
siege of badajoz


question:
Who played chemistry teacher Waiter White in the American TV series Breaking Bad?
answer:

breaking bad