Rainbow is produced when sunlight falls on drops of rain. Which of the following physical phenomena are responsible for this? 1. Dispersion 2. Refraction 3. Internal reflection Select the correct answer using the codes given below.

1. A rainbow is an optical and meteorological phenomenon produced when sunlight falls on drops of rain. 2. The formation of a rainbow involves several physical phenomena occurring as sunlight interacts with individual raindrops: a. Refraction (2): As sunlight enters a raindrop, it bends or refracts because it moves from air into water (a denser medium). b. Dispersion (1): As the white sunlight refracts upon entering the drop, it is separated into its constituent colours (spectrum) because different colours (wavelengths) of light bend at slightly different angles. This spreading of light into colours is called dispersion. c. Internal reflection (3): The dispersed light rays then travel to the back surface of the raindrop. A portion of this light undergoes total internal reflection off the back surface, bouncing back towards the front. d. Refraction (again): As the reflected light exits the raindrop back into the air, it refracts again, bending further. 3. The combination of these processes (refraction, dispersion, and internal reflection) causes the light exiting the raindrop to be separated into colours and directed back towards the observer at specific angles, forming the arc of a rainbow. 4. Therefore, all three phenomena – Dispersion, Refraction, and Internal reflection – are responsible for the formation of a rainbow.