Instructions: You are given a science question (easy-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.
Input: Magnesium strips are long, thin strips that are gray and shiny. Which action will lead to a chemical change of magnesium strips?
(A) putting them in the freezer (B) burning them with a candle (C) cutting them into small pieces (D) mixing them with pieces of copper
Output:
B