Answer: C

Attenuation is a signal degradation (decrease in amplitude) that occurs as a signal propagates along a transmission medium. This is seen particularly when the medium is copper wire. Noise is also a signal degradation that refers to a large amount of electrical fluctuation that can interfere with the interpretation of the signal by the receiver. Crosstalk is one example of noise where unwanted electrical coupling between adjacent lines causes the signal in one wire to be picked up by the signal in an adjacent wire. Delay distortion can result in a misinterpretation of a signal that results from transmitting a digital signal with varying frequency components. The various components arrive at the receiver with varying delays.   _{Your Comment}