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: The Smith family were preparing for Christmas. They needed to get a new tree. They bought a large pine tree from Walmart. They set the tree in their living room. Afterwards, they decorated the tree and put a star on top.
 selected sentence: They bought a large pine tree from Walmart.

The Smiths needed a new Christmas tree >Causes/Enables> They bought a large pine tree from Walmart