You are given a sentence and a question. You're expected to write the correct answer based on the sentence.

Example Input: Sentence: A stick of gum that is slid across a classroom desk travels pretty slow compared to a stick of gum that is pushed across a home office desk. Question: Which surface is the most rough?
Example Output: classroom desk

Example Input: Sentence: A bag of trash blows a little ways across the parking lot. Then it reaches a sidewalk. The bag blows all the way away from the building. Question: Which is less bumpy?
Example Output: sidewalk

Example Input: Sentence: A life vest floating in calm water has low friction while one floating in choppy water has high friction. Question: Which type of water will allow the life vest to float the furthest?
Example Output:
calm water