The driver of a patrol car must turn on to gain an advantage over other road users:
Blue color flashing beacon.
Blue and red flashing beacons.
The blue flashing beacon and the special sound signal.✓Bonne réponse
Explication
A patrol driver obtains priority over ordinary traffic only by using the blue flashing warning together with the special audible warning. A blue light alone identifies an urgent vehicle but does not create the full claim to priority tested here.