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.

Who is the original singer of nothing compares to you?
Prince Rogers Nelson

What player has the most super bowl appearances?
Tom Brady

When was cinderella written by the grimm brothers?

20 December 1812