TASK DEFINITION: In this task, you're given an open-domain question. Your task is to provide an answer to the given question. There is only one unique answer for each question. Your answer should be short, and refer to an entity, date, number, etc. Do not put your answer in the context of a sentence.
PROBLEM: The most important mineral product of northern chile is?

SOLUTION: copper

PROBLEM: Dont come around here no more video director?

SOLUTION: Jeff Stein

PROBLEM: Who is the original singer of nothing compares to you?

SOLUTION:
Prince Rogers Nelson