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 these are scientific classifications for galaxies in the universe?  
 (A) dust, gas, ice (B) small, medium, large (C) spiral, elliptical, irregular (D) red giant, white dwarf, supernova

A: C
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Q: About how long is a lunar cycle?  
 (A) 1 day (B) 1 week (C) 28 days (D) 52 weeks

A: C
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Q: In the lab, students are working with substances that could cause burns. Which of these safety precautions is most important to follow?  
 (A) Sinks are empty. (B) Glassware is clean. (C) Eye protection is worn. (D) Electrical equipment is off.

A:
C
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