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.

[EX Q]: 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
[EX A]: barn floor

[EX Q]: Sentence: A plunger gets a lot hotter plunging through a clogged toilet then plunging through a clean toilet. Question: Which surface will let the plunger go a greater distance per push? (A) clogged toilet (B) clean toilet
[EX A]: clean toilet

[EX Q]: Sentence: Neptune is one of the largest planets in the solar system. Question: Which object has stronger gravity? (A) Mercury (B) Neptune
[EX A]:
Neptune