Confidential Services Inc. is a military-support branch consisting of 1,400 computers with Internet access and 250 servers. All employees are required to have security clearances. From the options listed below, what access control model would be most appropriate for this organization? This task contains the radio buttons and checkboxes for options. The shortcut keys to perform this task are A to H and alt+1 to alt+9.

A.Discretionary access control
B.Role-based access control
C.Attribute-based access control
D.Mandatory access control