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.

Input: Consider Input: What determines how long the Moon takes to complete one cycle of phases?  
 (A) the period of rotation of the Moon around its axis (B) the period of revolution of the Moon around Earth (C) the period of rotation of Earth around its axis (D) the period of revolution of Earth around the Sun

Output: B


Input: Consider Input: A student pushes a box to slide it across the floor. Which statement explains why the box begins to move?  
 (A) The weight of the box is greater than the force of friction. (B) The weight of the box is less than the force of friction. (C) The applied force is greater than the force of friction. (D) The applied force is less than the force of friction.

Output: C


Input: Consider Input: The hypothesis of an expanding universe required which type of validation before being accepted as a significant part of scientific theory?  
 (A) a controlled single-variable laboratory test (B) support through evidence from numerous observations (C) proposal of alternative explanations with predictive value (D) a full-scale replication of each event in the proper sequence


Output: B