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:
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 Output:
B


Ex Input:
Which situation is the best example of an inherited trait?  
 (A) a boy playing with a ball (B) a bird building a nest (C) a horse pulling a wagon (D) a dog sitting on command

Ex Output:
B


Ex Input:
What can be inferred from a food product advertisement that claims "30% less fat than our leading competitors"?  
 (A) It is a sugar-free product. (B) It will help a person lose weight. (C) It is the healthiest choice available. (D) The fat content of the item is reduced.

Ex Output:

D