In the figure below, PQRS denotes the path followed by a ray of light as it travels through three media in succession. The absolute refractive indices of the media are µ1, µ2 and µ3 respectively. (The line segment RS' in the figure is parallel to PQ).
(A) µ1 > µ2 > µ3
(B) µ1 = µ3 < µ2
(C) µ1 < µ2 < µ3
(D) µ1 < µ3 < µ2