Ahhh...it seems the Gleim didn't cover it all (is that possible?) Maybe there is more to the topic than that required to meet CFI/AGI requirements...
The "Area Rule" typically relates to Form drag, also know as Boundry Layer Normal Pressure drag. Profile drag is a combination of Form drag and Surface Friction drag. So, the "area rule" is a component of Profile drag.
Wave drag is drag solely associated with shock wave formation, and is a different animal than Parasitic drag.