Definition: In this task, you will be given a short story. One sentence from the story is chosen. Consider the events that happen before that sentence, or are likely to have happened before it. Does any of them directly cause it, or simply make it possible? You should write your answer in the form " A >causes/enables> B". Try to use phrases and sentences from the story to compose your answer when possible.
Input: story: John didn't have many friends in his class. He had just moved earlier in the year. He was reading the book Tom Sawyer at recess. A boy walked up, telling him it was his favorite book. He and the boy ended up becoming friends after that.
 selected sentence: A boy walked up, telling him it was his favorite book.

The boy decides to walk up >Causes/Enables> The boy walks up