Answer:
The following options are available:
Dialog Box "Edit Surface"
Activate the "Hinges" tab (see Image 01) and use the button to create a new line hinge.
Types for Lines – Data Navigator
Right-click "Line Hinges" under "Types for Lines" in the Data Navigator, create a new line hinge, and assign it to the surface and line; see Image 02.
Types for Lines – Menu Bar
It is also possible to create a line hinge using the menu "Insert" → "Types for Lines" → "Line Hinges" → "Dialog Box".