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: What branch of biology creates models to make whole biological systems understandable?
Example Output: computational systems biology, systems biology and mathematical biology

Example Input: What does the rosenberg self esteem scale measure?
Example Output: self-esteem

Example Input: Walking dead is based on what comic book?
Example Output:
The Walking Dead