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:
A scientist combines oxygen and hydrogen to form water. This combination illustrates that water is  
 (A) an atom. (B) an element. (C) a mixture. (D) a compound.
answer:
D


question:
As Earth revolves around the Sun, the number of daylight hours varies from place to place. In which location would the number of daylight hours remain constant?  
 (A) North Pole (B) Prime Meridian (C) Equator (D) Antarctica
answer:
C


question:
Light sometimes behaves as waves and other times as particles. Which property of light is equally explainable by treating light as either particles or waves?  
 (A) interference of light (B) reflection of light (C) diffraction of light (D) polarization of light
answer:

B