You are given a science question (hard-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: Alan is using cabbage juice to determine the relative pH of various household solutions. Which of these steps communicates the results of his investigation?  
 (A) Conduct multiple trials (B) Write down a procedure (C) Identify the materials to be tested (D) Record observations and data in a journal

A: D
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Q: An athlete can run 9 kilometers in 1 hour. If the athlete runs at that same average speed for 30 minutes, how far will the athlete travel?      
 (A) 18 kilometers (B) 9 kilometers (C) 4.5 kilometers (D) 3.3 kilometers

A: C
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Q: Students are observing two fossils in a lab. They are told by the teacher that the fossils were found in different rock layers. What can the students most likely determine from just observing the fossils?  
 (A) how each organism died (B) the exact age of the fossils (C) when the fossils were discovered (D) the type of environment in which the organisms lived

A:
D
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