Arainbow is formed by refraction of light by separating light into all different colors, and rainbows are an optical phenomena due to the diffraction of light waves. Given these facts, a rainbow is formed by what into all different colors among the following options:
- movement
 - diffraction
 - photons
 - shaping
 - focusing a lens
 - recalling
 - sunlight
 - spreading


 

  diffraction       