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.

Example Input: Some scientists believe that the mass extinction of dinosaurs was caused by the impact of a large meteorite on Earth. This impact would have caused a darkening of the sky due to dust blown into the upper atmosphere. This darkening would have reduced the sizes of some ecosystems because of
(A) longer seasons. (B) accelerated erosion. (C) reduced photosynthesis. (D) increased number of hurricanes.
Example Output: C

Example Input: Which of these occurs if myosin fails to bind to actin during muscle contraction?
(A) The muscle cells will lose ATP. (B) The muscle cells will remain relaxed. (C) The muscle cells will produce lactic acid. (D) The muscle cells will lose calcium ions.
Example Output: B

Example Input: Where is most fresh (non-salty) water on Earth located?
(A) oceans (B) rivers (C) lakes (D) polar ice caps
Example Output:
D