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 properties best describes a material's ability to resist scratching?  
 (A) weight (B) flexibility (C) length (D) hardness

A: D
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Q: A student conducts an investigation using mold spores. In one part of the investigation, he needs to closely examine a spore sample. Which piece of equipment does the student need to use to keep mold spores from entering his respiratory system?  
 (A) breathing mask (B) safety goggles (C) rubber gloves (D) lead smock

A: A
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Q: Fossil fuels are considered a nonrenewable resource because they  
 (A) have turned into solid rock. (B) take a long period of time to form. (C) are expensive to remove from rock. (D) are located deep within the Earth's crust.

A:
B
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