__________ memory is the principal internal memory system of the computer.

Linux uses ________ to support authentication via interfaces including smart cards, Kerberos and voice authorization systems.

a) Linux security modules (LSMs) b) mandatory access control (MAC) c) pluggable authentication modules (PAMs) d) SELinux

Regarding enumerations, the ____ method returns an integer that represents the constant's position in the list of constants; as with arrays, the first position is 0.

A. valueAt B. positionOf C. ordinal D. indexOf