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: Cell mutations is the most common cause of cancer. Question: What is the most common cause of cancer?
Example Output: cell mutations

Example Input: Sentence: Mutation is essential in order for evolution to occur because it increases genetic variation and the potential for individuals to differ. Question: What phenomenon is essential in order for evolution to occur because it increases genetic variation and the potential for individuals to differ?
Example Output: mutation

Example Input: Sentence: A scallop is a(n) mollusk. Question: What type of creature is a scallop?
Example Output:
mollusk