What does this traffic sign indicate?

You selected the correct answer. This traffic sign means that motor vehicles with mandatory markings carrying dangerous goods are prohibited from entering. The orange sign on the vehicle in the symbol specifically indicates hazardous materials. This restriction helps protect areas from the increased risks associated with transporting dangerous goods. Knowing this, you can recognize that vehicles carrying such loads are not allowed past this sign, regardless of their weight or type, unless otherwise indicated. Other options such as prohibitions based on axle weight or just on trucks do not apply here.