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

[Q]: Which boxer was nicknames `The Brown Bomber`?
[A]: boxing


[Q]: Which instrument was Benny Goodman famous for playing?
[A]: benny goodman


[Q]: The Amazon river, the second longest in the world, drains into the Atlantic Ocean through what country?
[A]:
amazon river