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: In 1971, the bones of an extinct flying dinosaur were discovered. This kind of discovery helps everyone learn more about  
 (A) impact of humans on Earth. (B) effect of gravity on animals. (C) history of animal species on Earth. (D) likelihood that dinosaurs will reappear.
Example Output: C

Example Input: Some birds fly south in the fall and return in the spring. This is an example of  
 (A) migration (B) camouflage (C) hibernation (D) growth
Example Output: A

Example Input: A researcher observes that an organism placed in a glass container filled with water moves away when a penlight is focused on the container. The researcher concludes that the organism is light sensitive. Which other explanation for the organism's response to the light is most possible?  
 (A) The organism avoids radio waves. (B) The organism avoids gamma rays. (C) The organism moves away from vibrations. (D) The organism moves away from heat sources.
Example Output:
D