We cannot see in the fog, because

Correct option is D

The correct answer is (d) light becomes scattered by fog drops

Explanation:
• Fog consists of dense swarms of tiny suspended water droplets hanging in the air.
• When light from headlights or natural sources hits these droplets, it experiences scattering in virtually all random directions rather than traveling in straight lines.
• This intense scattering severely degrades contrast and ruins the visual perception of objects, resulting in poor visibility.

Information Booster:
• The scattering of light by suspended colloidal particles in a transparent medium is physically defined as the Tyndall effect.
• Fog lights on vehicles are typically placed low to the ground and have a wide beam specifically to cut under the fog layer and reduce back-scattering into the driver's eyes.

Additional Knowledge:
fog absorbs light (Option a)
• Water droplets in fog predominantly scatter visible light rather than absorbing its energy.
the refractive index of fog is infinite (Option b)
• This is physically impossible. The refractive index of liquid water is approximately 1.33, far from infinite.
there is complete reflection of light on fog drops (Option c)
• Total reflection implies a mirror-like bounce; scattering implies dispersion into randomized directions.
None of the above/More than one of the above (Option e)
• Incorrect, as light scattering is definitively the responsible optical phenomenon.

So the correct answer is (d)