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.

Example Input: Sentence: The acidity of a solution is typically assessed experimentally by measurement of its ph. Question: The acidity of a solution is typically assessed experimentally by measurement of its what?
Example Output: ph

Example Input: Sentence: A metallic bond is the force of attraction between a positive metal ion and valence electrons. Question: What is the force of attraction between a positive metal ion and valence electrons?
Example Output: metallic bond

Example Input: Sentence: Dinosaurs filled the niches that mammals fill today during the mesozoic era. Question: Dinosaurs filled the niches that mammals fill today during which era?
Example Output:
mesozoic