The panel indicates...
A)the distance between the sign and the beginning of the hazard.
B)the length of the stretch with two lanes in the same direction.
C)the length of the stretch of road affected by the hazard.Correct
The panel in the question indicates the length of the dangerous stretch. In the image in the question, we are warned that for 4.25 kilometres there is a stretch of dangerous bends close together, the first of them to the right.
On the other hand, when the panel does not show the two lateral arrows, it will indicate the distance to the beginning of the hazard.