From this sign onwards, travelling at a minimum of 30 kilometres per hour...
A)is recommended.
B)is prohibited.
C)is mandatory.Correct
The sign requires vehicle drivers to travel at least at the speed indicated in kilometres per hour, from the point where the sign is located until another "Minimum speed" sign with a different value, or an "End of minimum speed" or "Maximum speed" sign with an equal or lower value.
Do not confuse it with the recommended maximum speed sign, which advises an approximate travelling speed in km/h that it is recommended not to exceed, even when the meteorological, environmental, and traffic conditions on the road are favourable.