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: Proxima Centauri is the closest star to the Sun. Which units do astronomers most often use for the distance between Earth and Proxima Centauri?  
 (A) miles (B) meters (C) light years (D) astronomical units

A: C
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Q: Which would most likely be the characteristic of an object with a small volume and large mass?  
 (A) high density (B) low pressure (C) low viscosity (D) high temperature

A: A
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Q: Which of these organisms is classified as a decomposer?  
 (A) hawk (B) mushroom (C) mouse (D) grass

A:
B
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