Driver fatigue is most often caused by:
Correct. Sleep deprivation, long hours, and circadian-low night-driving hours are the leading causes of fatigue. Sleep before driving; pull over when drowsy.
CDL Practice Question #89
Category: General Knowledge
Why this question matters
This question is one of 97 in our General Knowledge bank. The reasoning above comes directly from the AAMVA CDL Manual, the source document used by every U.S. state DMV. Memorizing the underlying rule — not just the letter answer — is what separates passing on the first attempt from a return trip and another fee.