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

Ex Input:
Which Union leader of the American Civil War gave his name to a tree in California's 'Sequoia National Park'?

Ex Output:
american civil war

Ex Input:
In which Indian city is Eden Gardens, the second largest test cricket ground in the world?

Ex Output:
eden gardens

Ex Input:
David Seaman and David Beckham are connected with which sport?

Ex Output:
david beckham