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.

Ex Input:
Which is an example of an organism that has been selectively bred for a particular genetic trait?  
 (A) cats that eat mice (B) cows that graze on grass (C) pigs that form large herds (D) chickens that lay large eggs

Ex Output:
D


Ex Input:
Scientists use ice cores to identify and explain previous climatic trends. By correlating climatic conditions recorded in the ice, with solid, nonsnow particles also found in the ice, scientists can help to predict the climatic impact of which phenomena?  
 (A) atmospheric carbon dioxide concentration changes (B) radioactive decay rate changes in the outer core (C) volcanic eruptions (D) magnetic pole reversals

Ex Output:
C


Ex Input:
Oceans have many layers of sediments. These layers become compacted when they are buried under other layers of sediments. Which is most likely to happen to the deepest layers?  
 (A) They will be squeezed out onto deltas. (B) They will recrystallize into new rock. (C) They will become part of Earth's outer core. (D) They will melt in magma chambers.

Ex Output:

B