Which of the following is an incorrect way to avoid struck-by rolling hazards?

Which of the following is an incorrect way to avoid struck-by rolling hazards?
A. Position a worker to signal you when operating a vehicle in reverse gear without audible forward alarm
B. Set parking brakes when vehicles and equipment are parked, and chock the wheels if they are on an incline
C. Use traffic signs, barricades or flaggers when construction takes place near public roadways
D. Wear seat belts when provided