A. File Explorer, Documents, Downloads, Music, Pictures, Videos
B. All of A) plus HomeGroup, Network, and your Usersusername folder
C. All of the above plus C:, OneDrive, and This PC
D. All of the above plus Windows, Users, and Program Files.
There are 10 built-in icons (including Settings, which can be turned off), plus two that are required – Power and your User profile.