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

[EX Q]: Brasilia is the capital but which city in Brazil has the largest population?
[EX A]: brazil

[EX Q]: James Dearden wrote which book, made into a famous film directed by Adrian Lyne, in 1987?
[EX A]: adrian lyne

[EX Q]: Who directed the 1974 film `Chinatown`?
[EX A]:
chinatown