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 Q]: Your community is planning to build a new sanitary landfill. In locating the landfill, which is the most important environmental consideration?  
 (A) the cost of the land (B) the location of the groundwater (C) the proximity to an industrial park (D) the accessibility to a major highway
[EX A]: B

[EX Q]: Which of these substances is correctly identified as a mineral?  
 (A) coal (B) quartz (C) granite (D) sandstone
[EX A]: B

[EX Q]: On a day in early spring, the number of hours of daylight and of night are about the same. From sunrise to sunset on a spring day, Earth has  
 (A) completed half of one rotation. (B) been in the shadow of the Moon. (C) been circled by the Moon one time. (D) moved to the opposite side of the Sun.
[EX A]:
A