instruction:
Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
question:
What famous song from the film Butch Cassidy and the Sundance Kid won an Oscar for best song?
answer:
academy award for best original song

question:
What is the title of the four-episode special of 'Doctor Who', made for the Red Nose Day telethon in the UK, broadcast in March 1999?
answer:
doctor who

question:
Which of Verdi's operas tells the story of the hunchbacked jester to the 'Duke of Mantua'?
answer:
duke of mantua