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]: If the solar system were used as a model of an atom, what would the Sun most likely represent?  
 (A) an ion (B) a nucleus (C) a neutron (D) an electron
[EX A]: B

[EX Q]: Which could be a possible way to prevent wildlife species from becoming endangered?  
 (A) drinking less water (B) establishing more habitats (C) cutting down more forests (D) stopping underground coal mining
[EX A]: B

[EX Q]: Which of these lists has only products that come from plants?  
 (A) Paper, spices, and fibers (B) Wool, lumber, and butter (C) Medicines, leather, and milk (D) Cotton, rubber, and eggs
[EX A]:
A