instruction:
Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.
question:
Which singer played Billie Holiday in the 1972 film `Lady Sings The Blues`?
answer:
lady sings the blues


question:
The Brooklyn Bridge crosses which river?
answer:
brooklyn bridge


question:
Who won baseball's first World Series of the 50s?
answer:

baseball