Why should a driver be alert to the possibility of an unseen coupling failure between the trailers, particularly at highway speed?

Pick an answer

1. Coupling failures at highway speed are never a real concern
2. A separated trailer poses no danger to other vehicles
3. A failure could let a trailer separate from the combination and become an immediate hazard to other traffic
4. This risk only applies to the tractor's own coupling, never to the dolly's connection since the dolly is assumed to hold on its own regardless

Correct!

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