What do the seatbelt regulations require?

What do the seatbelt regulations require?
A)To carry it in the vehicle and only fasten it on the road.
B)To wear it unfastened.
C)To wear it fastened at all times.Correct
The use of a seatbelt is mandatory for the driver and passengers of passenger cars and those vehicles with a maximum authorised mass of up to 3,500 kilograms intended for the transport, simultaneous or not, of persons and goods.
To be effective and fulfil its function, the seatbelt must:
- Be approved (homologated).
- Be properly anchored.
- Be properly adjusted and fitted to the body.
- Be correctly fastened.
Poor adjustment of the seat or seatbelt can promote the submarine effect. This effect occurs when the seatbelt is unable to restrain the driver during an accident and their body slides under the abdominal strap.