The correct statement that describes the refraction of light is:
"As light waves enter a different medium, they bend towards the normal if they slow down and bend away from the normal if they speed up."
This means that when light travels from a medium with a lower refractive index (like air) to one with a higher refractive index (like water or glass), it slows down and bends towards the normal line. Conversely, when it moves from a medium with a higher refractive index to one with a lower refractive index, it speeds up and bends away from the normal line.