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

[EX Q]: Which Union leader of the American Civil War gave his name to a tree in California's 'Sequoia National Park'?
[EX A]: american civil war

[EX Q]: What American swimmer won eight gold medals at the 2008 Olympics?
[EX A]: 2008 summer olympics

[EX Q]: Who got to no.2 in the charts in 2002 with 'Cry Me a River'?
[EX A]:
cry me a river