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

[Q]: The Brooklyn Bridge crosses which river?
[A]: brooklyn bridge


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


[Q]: The early days of which sport featured the Renshaw twins, the Baddeley twins and the Doherty brothers?
[A]:
reginald doherty