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 of these are scientific classifications for galaxies in the universe?  
 (A) dust, gas, ice (B) small, medium, large (C) spiral, elliptical, irregular (D) red giant, white dwarf, supernova

Ex Output:
C


Ex Input:
When light is bounced off a mirror, the light is  
 (A) reflected. (B) refracted. (C) absorbed. (D) diffracted.

Ex Output:
A


Ex Input:
When an atom has a neutral charge, which particles within the atom have equal numbers?  
 (A) electrons and neutrons (B) protons and electrons (C) neutrons and protons (D) ions and neutrons

Ex Output:

B