instruction:
Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
question:
Which Chuck Berry song is performed by Marty McFly at the end of the film Back to the Future?
answer:
back to the future


question:
Allopurinol is typically prescribed for which illness?
answer:
allopurinol


question:
What AOL catchphrase is also the name of a Tom Hanks movie?
answer:

aol