Box 1: RG1, RG2, or RG3 -
The resource group stores metadata about the resources. When you specify a location for the resource group, you're specifying where that metadata is stored.
Box 2: West US only -
Note: Virtual machine scale sets will support 2 distinct orchestration modes:
ScaleSetVM - Virtual machine instances added to the scale set are based on the scale set configuration model. The virtual machine instance lifecycle - creation, update, deletion - is managed by the scale set.
VM (virtual machines) - Virtual machines created outside of the scale set can be explicitly added to the scaleset.
Reference:
https://docs.microsoft.com/en-us/azure/azure-resource-manager/management/overview
