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

Ex Input:
The rivers Axe, Brue, Cary, Parrett, eta, are in which English county?

Ex Output:
castle cary


Ex Input:
What is the main river of Brazil?

Ex Output:
brazil


Ex Input:
Which American General later President won the Battle of Horseshoe Bend?

Ex Output:

battle of horseshoe bend