The correct answer is that USB default setting is for recharge. The Hidden Menu can be enabled that will set up Dev Tools submenu. It has a MTB process toggle to enable selecting for various USB cable operations (eg, data transfer, FTP and photos only.
To enable the Hidden Menu: Go to settings, all the way to bottom. About Device>Tap multiple times on Build Number to activate it.
Thereafter, Developer Options Menu will show just below Security on main settings. Turn the toggle for this menu ON at the top of the page
The USB selection toggle is about half way down the list of available modules
DO NOT FOOL WITH ANY OTHER SETTINGS in this menu.
Once activated, when you plug in your USB, a popup menu will allow you to choose among USB settings.