You are given a sentence, a question and two answer options ('A' and 'B'). Your task is to find the correct answer (return the string of the correct option, not 'A' or 'B') for the given question.

Example Input: Sentence: A halter sliding across a barn floor gets hotter then one sliding across a field. Question: Which surface forces the halter to travel at a lower rate of speed? (A) barn floor (B) field
Example Output: barn floor

Example Input: Sentence: A microscope experiences less resistance when sliding across a lab table then when sliding across a lab floor. Question: Which surface will force the microscope to register less of an increase in temperature? (A) lab table (B) lab floor
Example Output: lab table

Example Input: Sentence: A billiard ball has a greater mass then a basketball. Question: Which ball has a stronger field of gravity? (A) billiard ball (B) basketball
Example Output:
billiard ball