What does the sign indicate?
A)That from the sign onwards traffic flows in two directions.
B)That the carriageway will be reduced to a single lane.
C)That the carriageway narrows on the right-hand side.Correct
The sign in the question indicates danger due to the proximity of a section of road where the carriageway narrows on the right-hand side.
When any of these 3 narrowing signs has a supplementary panel with metres attached to its lower part, it indicates the width of the narrowing so we know whether our vehicle can pass through. This only applies to these 3 signs. A supplementary panel below any other sign specifies the distance in metres at which we will encounter what the main sign is indicating.