What term describes a motor vehicle designed primarily to transport property, excluding passenger cars delivering US mail?

The term that accurately describes a motor vehicle designed primarily to transport property, while excluding passenger cars delivering US mail, is "commercial motor vehicle." This designation encompasses a range of vehicles used for commercial purposes, such as transporting goods or cargo. In the context of regulations and definitions, commercial motor vehicles are typically larger than standard passenger vehicles and often weigh over a specified limit, making them subject to different safety and operational standards.

The other options refer to specific types of vehicles within the broader category of commercial vehicles but do not encompass the definition as effectively. A light truck typically refers to a smaller truck designed for light-duty tasks and is often not classified under the same regulations as larger commercial vehicles. Heavy-duty vehicle signifies those used for substantial transportation tasks but does not necessarily delineate property transport specifically. A utility vehicle is generally designed for both passenger and cargo use, particularly in off-road situations, rather than primarily for transporting property. Thus, "commercial motor vehicle" is the most precise term for the context given.