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 Input:
Because copper is a metal, it is  
 (A) liquid at room temperature (B) nonreactive with other substances (C) a poor conductor of electricity (D) a good conductor of heat

Ex Output:
D


Ex Input:
Evidence of organisms that lived on Earth a long time ago would most likely be found in  
 (A) crystals. (B) lava. (C) sedimentary rock. (D) metamorphic rock.

Ex Output:
C


Ex Input:
Moving water was the most important factor in forming which of these?  
 (A) the Grand Canyon (B) San Andreas Fault (C) the Rocky Mountains (D) Mount St. Helens Volcano

Ex Output:

A