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.

Which object works best when reflecting light?  
 (A) mirror (B) camera (C) binoculars (D) eyeglasses
A

Spring tides occur during which lunar phases?  
 (A) first quarter and last quarter (B) full moon and new moon (C) when the moon is waxing (D) when the moon is waning
B

Based on analysis of deep ice cores from the Arctic, scientists theorize that early humans caused air pollution. These scientists can make sure their data is correct by  
 (A) analyzing only melted ice cores. (B) analyzing more than one ice core. (C) comparing their data to the expected results. (D) comparing their data to modern pollution levels.

B