Question

what is light?
a particle that has mass but no energy.
a type of sound wave that requires a medium.
an electromagnetic wave that carries energy.
a form of matter that has a fixed shape.

Explanation:

Light is classified as an electromagnetic wave that propagates through space (and can travel through a vacuum) while transferring energy. The other options are incorrect: light has no rest mass but carries energy, it is not a sound wave (sound requires a medium, light does not), and it is not matter with a fixed shape.

Answer:

C. An electromagnetic wave that carries energy.