You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For simplicity, answers should be in all lower cased letters.

Category: HOSPITALS 
Clue: The Cleveland Clinic tops U.S. News' 1996 ranking of hospitals in this, the study of the heart
cardiology

Category: THE 10 LARGEST COUNTRIES IN THE WORLD 
Clue: The one that spans 11 time zones
russia

Category: WOOD HOUSE 
Clue: You can visit the Boston house that this man left to go for a ride April 18, 1775

paul revere