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You feel alert after only 5 hours of sleep and coffee. Why should you still treat short sleep as a safety risk?
- A.Sleep loss impairs reaction time and judgment even when a driver feels awake, and caffeine does not restore performance
- B.Coffee fully replaces sleep for one shift
- C.Feeling alert proves performance is normal
- D.Short sleep only matters after three nights
Correct answer
A. Sleep loss impairs reaction time and judgment even when a driver feels awake, and caffeine does not restore performance
Why
Research and crash experience show that self-assessment is unreliable after sleep loss: people feel adapted while their responses keep slowing. Caffeine can raise alertness briefly but cannot restore the brain functions that sleep provides.
Manual topic: Fatigue - Sleep Loss · From the General Knowledge practice bank (GK-258).