This sign prohibits...
A)the passage of vehicles transporting more than 500 litres of products capable of contaminating water.
B)the passage of tanker vehicles.
C)the passage of vehicles transporting more than 1000 litres of products capable of contaminating water.Correct
The sign in the question prohibits the passage of all types of vehicles transporting more than 1000 litres of products capable of contaminating water.
Do not confuse it with the following sign, which prohibits the passage of vehicles transporting dangerous goods.