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: THE KOREAN WAR 
Clue: In bitter battles of 1951, Pork Chop was a hill & Heartbreak was one of these
ridge

Category: AMERICAN ART & ARTISTS 
Clue: Roy Lichtenstein perfected his technique for simulating benday dots to mimic the artwork found in these "strips"
comic strips

Category: ON LOCATION 
Clue: In 1998 "The X-Files" relocated to California from this Canadian city

vancouver