TASK DEFINITION: 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.
PROBLEM: Category: I GOT 3 As, MOM! 
Clue: In legend, this pure knight found the Holy Grail

SOLUTION: galahad

PROBLEM: Category: MUSIC 
Clue: Webster's defines this word as "a chord of three tones consisting of a root with its third and fifth"

SOLUTION: a triad

PROBLEM: Category: GREAT BRITS 
Clue: In the 17th century this British empirical philosopher opined, "No man's knowledge here can go beyond his experience"

SOLUTION:
john locke