Vehicles for persons with reduced mobility, if there is no road or part of it specially designated for them...
A)may travel on a highway.
B)may travel on a motorway.
C)must travel on the shoulder, provided it is passable and sufficient.Correct
# Explanation
Vehicles for people with reduced mobility must use the shoulder when there are no lanes specially designated for them. The shoulder is the lateral area of the road designed for these situations, provided it is in good condition and wide enough. On the other hand, these vehicles are prohibited from traveling on highways and motorways, which are fast roads not permitted for them.