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: Consider Input: Which energy source is considered nonrenewable?
(A) moving water (B) fossil fuel (C) wind (D) biomass

Output: B

Input: Consider Input: The greatest amount of diversity can be found among which type of organism?
(A) plants (B) animals (C) bacteria (D) fungi

Output: C

Input: Consider Input: Elizabeth uses a specific type of whistle to call her dogs. The noise made by the whistle is heard by the dogs but cannot be heard by the human ear. Which statement best describes why humans cannot hear the sound made by the whistle?
(A) The speed of the sound is too fast. (B) The amplitude of the sound is too low. (C) The frequency of the sound is too high. (D) The wavelength of the sound is too long.
Output: C