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 consistency, answers should be in all lower cased letters.

Category: ALL ABOARD AMTRAK 
Clue: The Keystone Route serves NYC, Philly & this capital; Three Mile Island's nearby if you're the nuclear plant gawker type
harrisburg

Category: BEST ACTRESS OSCAR BY FILM 
Clue: "Moonstruck"
cher

Category: SOUTH AMERICA 
Clue: Besides those of Spanish origin, they're Argentina's largest ethnic group

italians