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: A student walking quickly while carrying an orange on his lunch tray stops suddenly. The orange will most likely roll off the tray due to  
 (A) inertia of the orange. (B) centripetal force of the orange. (C) the friction acting on the orange. (D) the balanced forces acting on the orange.

A: A
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Q: A light year is used to measure  
 (A) time. (B) distance. (C) luminosity. (D) temperature.

A: B
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Q: Which of these provides the best evidence that an environmental change has occurred?  
 (A) a freshwater lake in the mountains (B) marine fossils in a freshwater lake (C) saltwater clams in the ocean (D) a sandy beach next to the ocean

A:
B
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