Question

Grouping the united states into the northeast region, the northwest region, the southeast region, and the southwest region would be departmentalization by

Answer 1

Grouping the united states into various regions would be departmentalization  by location.
Various organizations and entities use the departmentalization based on task, function or service etc. A divide which is based on various locations will be called departmentalization by location as it involves northeast, northwest, southeast and southwest locations.