On UNIX systems, passwords shall be kept:

A.
In any location on behalf of root.
B.
In a shadow password file.
C.
In the /etc/passwd file.
D.
In root.
Explanation:
When possible, on UNIX systems, passwords shall not be kept in the /etc/passwd file, but rather in a
shadow password file which can be modified only by root or a program executing on behalf of root.