In this task, you are given a sentence and a question, you would be asked to create the answer which is contained in the sentence provided.

Input: Consider Input: Sentence: Density describes how much matter is in a certain amount of space. Question: What describes how much matter is in a certain amount of space?

Output: density


Input: Consider Input: Sentence: Nuclear energy is released when the nucleus of an atom is split. Question: What kind of energy is released when the nucleus of an atom is split?

Output: nuclear


Input: Consider Input: Sentence: The outer surface of the heart changes from positive to negative during depolarization. Question: The outer surface of the heart changes from positive to negative during what?


Output: depolarization