The best response is: It connects cities that were established on the fall line.
The fall line is a geomorphological boundary in the eastern United States where the hard rocks of the Piedmont transition to the softer sediments of the Coastal Plain, often resulting in rapids and waterfalls. Cities along the fall line historically developed as important trade and transport hubs due to the presence of these natural features. Consequently, Interstate 95 was designed to connect these urban centers, following the path that aligns with the fall line.