Which two statements are true about the role based security model in Oracle Content Server?

Which two statements are true about the role based security model in Oracle Content Server?

A.
Initially, a new role is assigned Read, Write (RW) permission to the Public security group.

B.
One can assign multiple roles to a user.

C.
A role is a set of permissions for each security group.

D.
A permission is a set of roles for each security group.