What must a commercial driver possess while operating a vehicle?

Answer: C — valid CDL

To legally operate a commercial vehicle, a driver must hold a valid Commercial Driver's License (CDL). This specialized license ensures that the driver has undergone the necessary training and has demonstrated the knowledge and skills required to safely operate large and complex vehicles, which include trucks and buses. The requirements for obtaining a CDL involve passing both written and skills tests specific to commercial driving, covering areas such as vehicle operation, safety regulations, and handling hazardous materials, if applicable. Having a valid CDL is crucial for compliance with federal and state regulations governing commercial driving, and it also helps to ensure the safety of both the driver and others on the road. Without this license, a driver cannot legally operate commercial vehicles, making it essential for any individual in the commercial driving sector.