Problem Syncing Photo Folders From Mac to iPad

I am attempting to sync photo folders from my Mac laptop to iPad, through Finder via cable connection.  I checked the box ”Selected Folders” as I want to sync several folders at once, and not substitute any out.  When I select the “Choose Folder” screen option (Below), the screen with several folders comes up…but there are no check boxes such that I can select several folders to sync at once. I am thinking there is a simple solution, but I have not yet found it...

[Edited by Moderator]