Answer
None of the parts show physically possible refraction.
Work Step by Step
(a) When moving into a medium with a higher index of refraction, the diagram shows that the refracted angle of the red light is higher than the incident angle, which is not physically possible.
(b) When moving into another medium, the diagram shows that the refracted angle of the blue light is on the wrong side of the normal line to the surface boundary, which is not physically possible.
(c) The diagram shows that red light refracts more than blue light, which is not physically possible.
None of the parts show physically possible refraction.
