How can users be added to a Salesforce organization using Chatter Free?   Choose 2 answers

A.     Administrators can create users in the organization and assign them a Chatter Free license.
B.     Users and administrators can invite others outside of specified allowed email domains to join Chatter using Invites.
C.     Delegated administrators can invite others outside of the specified allowed email domains to join Chatter.
D.     Users and administrators can invite others within specified email domains to join Chatter using Invites.