This vehicle is immobilised due to a breakdown. Must you warn other road users?

This vehicle is immobilised due to a breakdown. Must you warn other road users?
A)On motorways and dual carriageways yes, on conventional roads no.
B)No, because the vehicle is not a lorry.
C)Yes, with the hazard pre-warning device and the hazard warning lights.Correct
To warn of the presence on the road of any obstacle or hazard created, the person responsible for it must signal it effectively both by day and by night.
If the obstacle is caused by the immobilisation of the vehicle or the falling of its load, where applicable, the person responsible shall signal it with the position lights and the hazard warning light if the vehicle has one.
While the road is being cleared, every driver shall place the hazard pre-warning device to warn of said obstacle.
The V-16 hazard pre-warning device is an amber-coloured luminous device, approved and with geolocation, that operates on autonomous power (battery or cell). It must be placed on the highest part of the immobilised vehicle, ensuring maximum visibility. Currently, the V-16 is the only legal option for signalling an immobilised vehicle or an obstacle on the road, with warning triangles now obsolete.