Drivers should use their low beam headlights:
- When driving in fog, dust, or rain.
- When following closely behind another vehicle at night.
- Within 500 feet of an approaching vehicle when driving at night.
- All of the above. ✓
Answer: D. All of the above.
Drivers should use low beam headlights in all of the listed situations: in fog, dust, or rain; when following closely behind another vehicle at night; and within 500 feet of an approaching vehicle at night.
Why this is the answer
The handbook lists low beams for exactly these conditions. It says to use low beams when you are within 500 feet of an approaching vehicle, when you are following closely (within 300 feet) behind another vehicle, and when driving in fog, heavy rain, sleet, snow, or dust. It also lists lighted roads. Because each situation in the question appears on that low-beam list, the complete answer is all of the listed choices. The rule is about when low beams are required or advised, not about using high beams.
Why the other answers are wrong
- A. When driving in fog, dust, or rain. — Using low beams in fog, dust, or rain is correct, but it is only one part of the handbook's low-beam list, so it is incomplete as the full answer.
- B. When following closely behind another vehicle at night. — Following closely behind another vehicle at night is one listed low-beam situation, but choosing only it leaves out the other situations.
- C. Within 500 feet of an approaching vehicle when driving at night. — Being within 500 feet of an approaching vehicle at night is one listed low-beam situation, but choosing only it leaves out the other situations.
Remember it
Think "close and cloudy": low beams when someone is close ahead or oncoming, and when fog, rain, or dust cuts visibility.