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: Who was the pale rider supposed to be?

SOLUTION: Thanatos

PROBLEM: What branch of biology creates models to make whole biological systems understandable?

SOLUTION: computational systems biology, systems biology and mathematical biology

PROBLEM: Who played belle in beauty and the beast 2017?

SOLUTION:
Emma Watson