An Oracle Cloud Infrastructure tenancy administrator is not able to delete a user in the tenancy. What can cause this issue? 

Answer options:

A. User has multi-factor authentication (MFA) enabled.
B. User is member of an Identity and Access Management (IAM) group.
C. Users can be blocked but not deleted.
D. User needs to be deleted from federation Identity Provider (IdP) before deleting from IAM.

A