The road sign shown prohibits travel:

• 1Trucks whose overall width (with or without a load) is greater than that indicated on the sign.
• 2Of buses whose width is greater than that indicated on the sign.
• 3Of tractors and self-propelled machines and mechanisms whose overall width (with or without cargo) is greater than that indicated on the sign.
• 4Of all vehicles whose overall width (with or without a load) is greater than that indicated on the sign.