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.

Q: The nucleus of MOST atoms consists of  
 (A) neutrons only (B) protons and neutrons (C) protons and electrons (D) neutrons and electrons

A: B
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Q: One substance found on Earth is more stable as an elemental gas than as part of a solid compound. As a result, this substance is very abundant in the atmosphere. Which substance exhibits these traits?  
 (A) argon (B) chlorine (C) nitrogen (D) oxygen

A: C
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Q: Which material is the best conductor of electricity?  
 (A) metal (B) glass (C) wood (D) plastic

A:
A
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