Respuesta :
Its A. Without someone there to navigate you someone can get ran over and have a strucky by rolling
The answer is: A.Position a worker to signal you when operating a vehicle in reverse gear without audible forward alarm
When operating vehicle in reverse gear, the operator cannot always see whether the worker who gives the signal able to see the moving vehicles or not.
Which is why an audible sound for moving vehicles is needed so the other workers could notify the location of your vehicles and avoid themselves from being crushed.