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 Q]: Living things are classified as producers or consumers according to  
 (A) their speed of movement (B) the size of their communities (C) how they obtain food (D) how they reproduce
[EX A]: C

[EX Q]: 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 A]: C

[EX Q]: Which is a process that occurs during photosynthesis?  
 (A) Plants take in oxygen and release sugar. (B) Plants take in sugar and release minerals. (C) Plants take in minerals and release carbon dioxide. (D) Plants take in carbon dioxide and release oxygen.
[EX A]:
D