What does this sign indicate?

A)Entry prohibited for vehicles transporting dangerous goods.
B)Mandatory road for vehicles transporting explosive goods.
C)Entry prohibited for vehicles transporting explosive or flammable goods.Correct
The sign in the question prohibits entry to all types of vehicles transporting explosive or highly flammable goods that must travel in accordance with their special regulations.
Do not confuse with signs that prohibit entry to vehicles transporting dangerous goods or water-polluting products in quantities exceeding 1000 litres.