The typical reaction time for an alert driver is about 0.75 seconds. Which option matches this value?

• A. 1.25 seconds
• B. 2.0 seconds
• C. 0.25 seconds
• D. 0.75 seconds

Answer: (D)

Reaction time is the interval between seeing a hazard and starting to react. For an alert driver, about 0.75 seconds is typical, so the value that matches this is 0.75 seconds. This means it takes roughly three-quarters of a second to recognize the danger, decide what to do, and begin to move. The longer options (1.25 or 2.0 seconds) would indicate slower than average reaction, increasing your stopping distance. The shorter option (0.25 seconds) would be unusually fast and not representative of normal human reaction. Remember, this reaction time is just the initial part; total stopping distance also includes the braking distance after you begin to act.