Question: A beam of light passes from medium 1 to medium 2 to medium 3 as shown in the diagram. What may be concluded about the speed of light in each medium? A) v_3 > v_1 > v_2  B) v_1 > v_2 > v_3  C) v_1 > v_3 < v_2  D) v_2 > v_3 > v_1. Please choose an answer from [A, B, C, D].
Answer: A