What is a decrease in amplitude as a signal propagates along a transmission medium BEST known as?

A.
Crosstalk

B.
Noise

C.
Delay distortion

D.
Attenuation

Explanation:
Attenuation is the loss of signal strength (amplitude) as it travels. The longer a cable, the more attenuation
occurs, which causes the signal carrying the data to deteriorate. This
Incorrect Answers:
A: Crosstalk is not decrease in amplitude. Crosstalk is a phenomenon that occurs when electrical signals of one
wire spill over to the signals of another wire.
B: Loss in signal strength is called attenuation. Noise does not affect signal strength.
C: Delay distortion does not affect signal strength.

Harris, Shon, All In One CISSP Exam Guide, 6th Edition, McGraw-Hill, New York, 2013, p. 561