You will be given a passage with an enumerated set of facts, a question of form 'Where is <person_name>?', and its answer. The task is to identify a supporting fact that is necessary to answer the question. The output would be the corresponding fact number.
Q: Passage: Fact 1- Sandra travelled to the hallway. Fact 2- Mary moved to the office. Fact 3- John went back to the kitchen. Fact 4- John went to the office. Fact 5- Mary went back to the kitchen. Fact 6- John journeyed to the hallway. Question: Where is Mary? Answer: kitchen
A: 
Fact 5