instruction:
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.
question:
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
answer:
B


question:
At what time on a sunny day will the shadow of the school's flagpole be the shortest?  
 (A) sunrise (B) noon (C) mid-afternoon (D) sunset
answer:
B


question:
Which of the following would most likely result in an abnormal chromosome number?  
 (A) The deletion of DNA during translation. (B) Mutations occurring during the blastula stage. (C) DNA exposed to radiation after the birth of the organism. (D) Failure of homologous chromosomes to separate during meiosis.
answer:

D