What is the purpose of the validuser ACL?

A.
When a user transmits data through the controller, the validuser ACL is used to check if the user is in the layer 3 user-table
B.
Before a client is added to the controller’s user table, the validuser ACL is checked to make sure the client has a valid IP address
C.
The validuser ACL is used during 802.1X authentication to check that the client is in the layer 3 user-table
D.
When an AP needs to transmit data to a user, it checks the validuser ACL to make sure the user has a valid IP address
E.
A list of configured MAC addresses that define the valid users