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.

Example Input: Who's the best selling artist of all time?
Example Output: The Beatles

Example Input: Which african american led the back to africa movement during the early 20th century?
Example Output: Marcus Mosiah Garvey Jr.

Example Input: Who discovered that energy travels in discrete units that he called quanta?
Example Output:
Max Planck