instruction:
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.
question:
Category: PREHISTORIC TIMES 
Clue: The Stone Age lasted until this metal replaced stone as the primary tool-making material
answer:
bronze


question:
Category: ARTISTS & THEIR SUBJECTS 
Clue: Augustus John, known for his portrait of this Welsh poet, introduced the poet to his future wife Caitlin
answer:
dylan thomas


question:
Category: ACTORS IN '50s FILMS 
Clue: He played Billy the Kid in "The Left-Handed Gun" in 1958, 11 years before he starred as Butch Cassidy
answer:

paul newman