What is prohibited by a "No motor vehicles" traffic sign?

A "No motor vehicles" traffic sign indicates that all motorized vehicles are prohibited from entering a specific area. This includes cars, motorcycles, trucks, and any other vehicle that operates using an engine. The purpose of this sign is typically to limit access to certain areas for safety reasons, environmental protections, or to prioritize pedestrian or non-motorized traffic.

In contrast, the other options specify restrictions on certain types of vehicles rather than all motorized vehicles. Therefore, while large trucks and motorcycles may be included under the broader category of motorized vehicles, the sign’s prohibition applies universally to any vehicle that is powered by an engine, reinforcing the understanding that the restriction is comprehensive and not selective. Bicycles, being human-powered and not motorized, are generally allowed in areas marked by this sign unless indicated otherwise by additional signage.