Explanation

(c) The blue colour of sky is due to Rayleight’s scattering $\left( \propto \frac{1}{\lambda^{4}} \right)$
As light moves through the atmosphere, most of the longer wavelengths pass straight through, little of the red, orange and yellow light is affected by air. However, much of the shorter wavelength light (blue) is absorbed by the gas molecules. The absorbed blue light is then radiated in different directions. It gets scattered all around the sky and hence sky appears blue. In order, that sky appears red will be possible if atmospheric particles scatter red light more than blue light.