Which of the following is a severe traffic violation that could impact a CMV driver?

Driving under the influence of alcohol is classified as a severe traffic violation for a Commercial Motor Vehicle (CMV) driver. This offense not only poses significant risks to public safety but also carries harsh penalties and consequences. A CMV driver found operating their vehicle with a blood alcohol concentration above the legal limit is subject to license suspension, fines, and potential criminal charges. Due to the larger size and weight of commercial vehicles, the risks associated with impaired driving are significantly greater, making this violation particularly critical in terms of safety regulations within the commercial driving industry.

In contrast, the other options, while violations, do not carry the same severe implications for CMV drivers. Driving with an expired vehicle registration is typically a regulatory issue and may lead to fines but does not directly endanger public safety in the same way. Using the vehicle for personal errands, while often against company policy, does not carry the same legal repercussions. Parking in a restricted area is typically a local traffic ordinance infraction that may lead to tickets but does not have the significant legal implications or safety concerns associated with impaired driving.