How can this custom form be made available within ArcMap?

For a project, an ArcGlS user creates a custom user interface form to allow data entry and editing directly with the database. This form must be available within ArcMap and also as a stand-alone tool.

How can this custom form be made available within ArcMap?
A . as a layer package
B . as a custom transformer
C . as an add-in
D . as an ArcPy Python script

Answer: D