Q.   How can the component that was right clicked be determined while in an event handler of a popup MenuItem?

A.    Use the PopupComponent property of the PopupMenu component to determine what control was right clicked.

procedure TForm1.PopupItem1Click(Sender: TObject);
begin
  Label1.Caption := PopupMenu1.PopupComponent.ClassName;
end;

      The form's ActiveControl property can also be used, however,  the active control may not necessarily be the control that caused the popup menu to appear.