Light is an electromagnetic wave which can travel in vacuum as well as any medium. The speed of light is maximum in vacuum. The electromagnetic wave travels by oscillating electric and magnetic field to the direction of motion of wave.
On the other hand, sound waves are mechanical waves which can only travel in a medium as they can only move forward by oscillating material particles.
Its D: Tightly packed particles in solids slow down the light waves; however, sound waves make particles bounce into each other, so they travel faster in solids.
