Dispersion of white light in a prism Steps:

• White light enters prism and refracts at the boundary due to change in medium.
• Different colors (wavelengths) have varying speeds in glass, causing unequal refraction angles.
• This separation of colors is dispersion, while bending is refraction.
• Light speed decreases inside prism compared to air.

Why C is correct:

• Dispersion separates colors via wavelength-dependent refraction (Snell's law: n varies with λ), and speed is smaller in denser medium (v = c/n, n > 1).

Why the others are wrong:

• A: Involves refraction and dispersion, not just wave properties like interference.
• B: Omits refraction, which causes the bending essential to the path.
• D: Speed is smaller in prism, not greater.

Final answer: C