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.

Example Input: Four objects are on a wooden ramp. Which object is most likely to roll off the ramp if it is pushed gently?  
 (A) flat eraser (B) round ball (C) bent paper clip (D) wooden cube
Example Output: B

Example Input: Sam looks into a fish pond and points at a goldfish. Sam's grandfather looks where Sam is pointing and tells Sam that the fish is actually in a different location. Which property of light explains why Sam's grandfather is correct?  
 (A) reflection (B) refraction (C) diffraction (D) absorption
Example Output: B

Example Input: Which of these tectonic plate boundaries is most likely to form a volcano?  
 (A) a continental plate colliding with a continental plate (B) an oceanic plate sliding past a continental plate (C) a continental plate sliding past a continental plate (D) an oceanic plate colliding into a continental plate
Example Output:
D