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: Fred went backpacking in the mountains for the weekend. Every night he hung the bag of food in a tree for bear proofing. One night he forgot to remove a candy bar from his backpack. A bear came during the night and tore apart Fred's backpack. He had to carry his gear in his sleeping bag for the rest of the trip.
 selected sentence: Every night he hung the bag of food in a tree for bear proofing.

Fred goes backpacking in the mountains >Causes/Enables> Fred hangs the bag of food in a tree for bear proofing