When is the use of a safety chain required?

Answer: B — When towing a trailer to connect the trailer's coupling to the towing vehicle

The use of a safety chain is required when towing a trailer as a means to ensure that if the primary coupling fails, the trailer will still be attached to the towing vehicle. Safety chains provide a secondary connection that is crucial for maintaining control of the trailer and preventing accidents. In this scenario, the safety chain acts as a fail-safe measure, enhancing overall safety during transport. Towing laws and safety regulations mandate this practice to reduce the risk of a trailer detaching unexpectedly, which can lead to serious accidents. While it is essential to follow appropriate safety measures any time a load is being towed, the requirement specifically focuses on maintaining that secure connection between the trailer and the vehicle, making the use of safety chains necessary.