Dispersion of white light by a glass prism occurs because

• A.White light consists of a mixture of seven different colours
• B. The refractive index of glass if different for each constituent colour of white light
• C. The speed of each colour of light in the glass is proportional to the refractive index of glass for each colour
• D. The speed of each colour of light in the glass is proportional to the angle of refraction in the prism