What is the primary operational hazard of transporting bulk grain or loose aggregate loads without using an approved tarpaulin / cargo cover (lona / toldo de cobertura)?

1. The vehicle will consume 50% less fuel
2. Grain and stone aggregate blows off into following traffic, shattering windshields, causing motorcycle crashes, and spilling cargo across the roadway
3. The truck's suspension air bags will over-inflate
4. The grain will spoil immediately from engine noise