Detailed Instructions: 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.
Q: Sentence: A steel ball has a greater mass then a pebble. Question: Which object has a stronger gravitational field? (A) steel ball (B) pebble
A:
steel ball