Correct option is C
Blue colour of the sky is an example of scattering of light.
· Blue colour of the sky: The blue color of the sky is a classic example of scattering of light. Shorter wavelengths of light, such as blue and violet, are scattered more than longer wavelengths (red and yellow) by molecules and particles in the atmosphere. As a result, when sunlight enters the Earth's atmosphere, the blue and violet components are scattered in all directions, making the sky appear predominantly blue.
· The twinkling of a star is due to atmospheric refraction of starlight. The starlight, on entering the earth's atmosphere, undergoes refraction continuously before it reaches the earth. The atmospheric refraction occurs in a medium of gradually changing refractive index.
· When white light is passed through a glass prism it splits into its spectrum of colours (in order violet, indigo, blue, green, yellow, orange and red) and this process of white light splitting into its constituent colours is termed as dispersion.