Communications and network security relates to transmission of which of the following?

A.
voice

B.
voice and multimedia

C.
data and multimedia

D.
voice, data and multimedia

Explanation:
Security applies to all types of transmitted data whether it is voice, data or multimedia.
Incorrect Answers:
A: Not only voice transfer must be secure. Data and multimedia transmission must be secure as well.
B: Not only voice and multimedia transfers must be secure. Data transmission must be secure as well.
C: Not only data and multimedia transfers must be secure. Voice transmission must be secure as well.

Harris, Shon, All In One CISSP Exam Guide, 6th Edition, McGraw-Hill, New York, 2013, p. 515