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: Early scientists most likely saw a discharge of electricity for the first time when observing a  
 (A) waterfall (B) rainbow (C) lightning storm (D) volcano erupting
Example Output: C

Example Input: Scientists are able to conclude that a forested ecosystem existed in Antarctica millions of years ago by studying  
 (A) the current climate. (B) the fossil record. (C) glacial movement. (D) seafloor spreading.
Example Output:
B