Rainbow formation is as a result of the combination of which of the following phenomena? (i) Reflect

Sunlight enters a raindrop and is refracted (bent). Because each colour bends by a different amount, the white light is split into colours. This is dispersion.

The light then hits the back of the drop at an angle bigger than the critical angle, so it is totally internally reflected. It leaves the drop and is refracted again.

So the answer is dispersion, total internal reflection and refraction. Plain reflection alone is not listed as a step because the back-surface reflection is total internal reflection.