Q: You are given a science question (hard-level) and four answer options (associated with "A", "B", "C", "D"). Your task is to find the correct answer based on scientific facts, knowledge, and reasoning. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D'. There is only one correct answer for each question.
Mr. Garcia's science class was studying energy and ways to cut energy costs. Each student was to compare their electric bill for October to the one they would receive for November. Each student would have a list of energy-saving tips that they would follow during November. Which would be the most uncontrollable factor in their investigation?
(A) the list of energy-saving tips to follow (B) the outdoor temperature in November (C) the amount of time given to the investigation (D) the accuracy of the October and November bills
A:
B