Which is the minimum CDL class required to operate a single unit vehicle with a GVWR of 26,001 or more, or any such vehicle towing another vehicle of 10,000 lbs GVWR or less?

Answer: B — Class B

To operate a single unit vehicle with a Gross Vehicle Weight Rating (GVWR) of 26,001 lbs or more, or to tow a vehicle with a GVWR of 10,000 lbs or less, a Class B Commercial Driver's License (CDL) is required. This license is specifically designed for individuals who drive larger vehicles that don’t fall under the more stringent requirements of a Class A license, which is meant for combination vehicles. A Class B CDL permits the operation of vehicles such as large trucks, buses, or those designed to carry heavy loads, but it does not allow the operation of vehicles that exceed the criteria specified for Class A. Therefore, the Class B license is the appropriate classification for the scenario presented in the question. In contrast, Class A and Class C licenses pertain to different vehicle configurations, while a Class D typically refers to a standard non-commercial driver's license, which does not meet the requirements for operating the specified commercial vehicle.