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: Clark was a simple clerk in a grocery store. One day he ran through the aisles in a shopping cart. He crashed into a shelf, and it hit the other shelves. Every shelf in the market crashed. Clark was fired, no longer a clerk, just Clark.
 selected sentence: Every shelf in the market crashed.

A shelf crashes into the other shelves >Causes/Enables> The other shelves crash