How far should low beam headlights be visible in rain or fog?

Answer: B — 150 feet

In rain or fog, low beam headlights are designed to illuminate the road ahead within a shorter, safer distance because moisture scatters light and can create glare. The recommended visibility distance for these conditions is about 150 feet, which gives you enough time to spot hazards and react while minimizing glare for others. Distances like 50 feet are too short for safe reaction, and 300 or 450 feet aren’t reliable in fog because the beam doesn’t travel clearly through dense droplets. If you can’t see roughly 150 feet ahead with low beams, slow down and increase following distance.