Given a factoid/trivia type question, generate the topic of the question. The topic is the entity the question talks about.

[EX Q]: I which European city will you find 'Dam Square'?
[EX A]: dam square

[EX Q]: Who directed the film `Back To The Future`?
[EX A]: back to the future

[EX Q]: Which Canadian born  actress was the star in the movie Barb Wire?
[EX A]:
barb wire