Question

which of the following statements regarding the quantum theory of light is correct?
light can only travel as a wave
light is composed of discrete particles with mass
light travels as waves with mass
light is composed of discrete mass - less particles
light is neither particle - like or wave - like

Explanation:

Quantum theory of light states light has wave-particle duality. Photons (light particles) are discrete and massless.

Answer:

Light is composed of discrete mass-less particles