Within built-up areas, is the use of acoustic warnings permitted?

A)Yes, exclusively to avoid an accident.
B)No.
C)Yes, to avoid an accident or to warn other road users that an emergency service is being carried out.Correct
Acoustic warnings may be used both within and outside built-up areas: - To avoid accidents or collisions with pedestrians. - When carrying out an urgent service. - On narrow roads with many bends. And to warn of an overtaking manoeuvre, but only on interurban roads.