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: Which of the following correctly lists the organizational hierarchy of organisms from simplest to most complex?  
 (A) cells, organs, tissues, organ systems, organisms (B) cells, tissues, organs, organ systems, organisms (C) tissues, cells, organs, organ systems, organisms (D) tissues, organs, cells, organ systems, organisms

A: B
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Q: What is an environmental threat posed by oil and gas acquisition and transport that is not posed by the acquisition and transport of the energy resources uranium, and wood?  
 (A) habitat change (B) vehicle pollution (C) pipeline leaks (D) soil compaction and loss

A: C
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Q: Ninety-nine percent of the mass of an atom is located in  
 (A) the outermost energy level. (B) the first energy level. (C) the electron clouds. (D) the nucleus.

A:
D
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