Guards are appropriate whenever the function required by the security program involves which of
the following?

A.
The use of discriminating judgment.

B.
The use of physical force.

C.
The operation of access control devices.

D.
The need to detect unauthorized access.

Explanation:
This is the correct answer, we don’t have guards only to use physical force, that is
not the real functionality of them if your security policy is well oriented. They are not only there to
operate control devices and to detect unauthorized access, as stated in CISSP documentation, the
appropriate function of a guard inside a security program is the use of discriminating judgment.