What items must be secured on the vehicle?

The correct answer encompasses the requirement that not just the cargo, but all items carried on the vehicle must be securely fastened to prevent them from becoming hazards on the road. This includes not only the primary cargo but also any additional items such as gas cans, tools, wheel chocks, or other equipment that might be affected by movement during transportation.

Securing all items is crucial for safety, as unsecured objects can shift due to sudden stopping or turns, potentially leading to accidents or damaging the load. This not only protects the driver and other road users but also ensures compliance with safety regulations, which mandate that all parts of the load, whether bulk cargo or individual items, must be secure.

Other responses focus on limited aspects, suggesting that only certain elements need attention. For instance, the idea of securing only the cargo ignores the risk posed by loose items that could shift or be ejected from the vehicle, while the reference to just the spare tire or cabin items is insufficient to maintain overall safety. Therefore, option B correctly emphasizes the importance of securing the entire load and all associated items to ensure complete safety while operating the vehicle.