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 season is the Northern Hemisphere experiencing when it is tilted away from the Sun?  
 (A) spring (B) summer (C) autumn (D) winter
answer:
D


question:
Two atoms of oxygen combine to form pure oxygen gas. What is the electrical charge of the O_{2} molecules?  
 (A) positive (B) negative (C) neutral (D) variable
answer:
C


question:
Which resource, abundant in Nevada, is nonrenewable?  
 (A) copper (B) wind (C) sunlight (D) wood
answer:

A