What characterizes a through highway?

A through highway is characterized by having traffic that enjoys a preferential right-of-way, meaning vehicles traveling on this type of highway have the right to continue without stopping, while vehicles on intersecting roads must yield. This designation helps facilitate smoother and more efficient traffic flow, as it minimizes the likelihood of interruptions caused by stop signs or traffic signals.

The other options do not accurately capture the essence of a through highway. For instance, while a highway may indeed not have stop signs or signals, this alone does not define it as a through highway, especially since a highway could lack such signals yet still have traffic that does not have a preferential right-of-way. The option suggesting that a through highway is limited to commercial vehicles misrepresents the classification, as through highways can serve all types of traffic, not just commercial. Lastly, a multi-lane highway designated for fast travel specifies the number of lanes and the intended speed but does not encompass the concept of right-of-way that is crucial to defining a through highway.