The correct answer is Monoalphabetic cipher. It uses one alphabet shifted three places.
Answers Polyalphabetic cipher and Transposition cipher are incorrect because in answer a,
multiple alphabets
are used and in answer Transposition cipher, the letters of the message are transposed.
Answer Code group is incorrect because code groups deal with words
and phrases and ciphers deal with bits or letters.

The correct answer is "To ensure that system changes are implemented in an orderly manner".
Answer "To guarantee that an operator is only given the privileges needed for
the task" describes least privilege.
Answer "To guarantee that transaction records are retained IAW compliance requirements"
describes record retention.
Answer "To assign parts of security-sensitive tasks to more than one individual" describes
separation on duties.

The correct answer is Employees. Internal personnel far and away constitute the largest amount of dollar loss due to unauthorized or inappropriate computer use.

Simple Mail Transfer Protocol (SMTP) is a protocol for sending e-mail messages between servers. POP is a protocol used to retrieve e-mail from a mail server. NFS is a TCP/IP client/server application developed by Sun that enables different types of file systems to interoperate regardless of operating system or network architecture. FTP is the protocol that is used to facilitate file transfer between two machines. Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, 2001, John Wiley & Sons, Page 88.