Which of the following are Cisco IOS privilege levels that are not typically assigned by default? (Select 3 choices.)
A. 1

B. 5

C. 7

D. 10

E. 15

Explanation:
Of the available choices, privilege levels 5, 7, and 10 are custom privilege levels and are not typically assigned by default. Privilege levels can be used to limit the IOS commands that a user can access. However, you are limited to 16 privilege levels, some of which are used by default by the IOS. For example, privilege levels 1 and 15 are default IOS privilege levels. Privilege level 1 allows a user to issue any command that is available at the user EXEC > prompt. Privilege level 15 allows a user to issue any command that is available at the privileged EXEC # prompt. The highest level of access on a Cisco router is provided by IOS privilege level 15.
Each privilege level is associated with a list of commands that are available at that level. Users assigned to a privilege level have access to all of the commands at that privilege level and all lower privilege levels. Changing the commands that are available to a privilege level might provide access to a user who should not be allowed access to the command, or it might restrict access to another user who should be allowed access to the command.
Because the default privilege level for a newly created local user account is 1, a newly created user will always have access to the disable, enable, exit, help, and logout commands? These commands are associated with a privilege level of 0. However, peruser privilege levels can sometimes conflict with the privilege levels set for virtual terminal (VTY) interfaces. In the event of a conflict, per user privileges override the privileges configured for the VTY line causing the conflict.
Reference:
CCNA Security 210260 Official Cert Guide, Chapter 11, Custom Privilege Levels, p. 287
Cisco: IOS Privilege Levels Cannot See Complete Running Configuration: Privilege Levels