To pass an obstacle, can you move into the adjacent lane?
A)No, under no circumstances.
B)Yes, whether or not the other lane is occupied.
C)Yes, provided that lane is not occupied.Correct
When, on a section of road where overtaking is prohibited, there is an obstacle or a vehicle immobilised for reasons unrelated to traffic (breakdown, accident or other emergency) that occupies the lane in the direction of travel, it may be passed even if it is necessary to occupy part of the lane intended for the opposite direction, provided that you have first made sure that the manoeuvre can be carried out safely.
Passing an immobilised vehicle or an obstacle is not considered overtaking but passing.