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: LETHAL WEAPONS
Clue: In the largest man-made explosion in history, the USSR detonated a 50-megaton one of these in 1961
a hydrogen bomb

Category: ART & ARTISTS
Clue: This "Joy of Life" Fauvist studied law, but turned to painting when recuperating from an operation (Good choice!)
henri matisse

Category: QUOTATIONS
Clue: Karl Marx: this "is the opium of the people"
religion