When a ray of light passes from a rarer medium to a denser medium, it:
Correct: B
According to the laws of refraction, when light travels from an optically rarer medium (like air) to an optically denser medium (like glass or water), its speed decreases, and it bends towards the normal at the interface between the two media. Conversely, it bends away from the normal when passing from a denser to a rarer medium.