Answer: Increase in amplitude
Step-by-step explanation: Amplitude is used for the determining the Radio-frequency(RF) signal's strength. The replacement of the cluster of cables with a cable having shorter length will effect the RF signal by increasing the amplitude.
The amplitude varies with the intensity of the sound usually and is related with the power as well .So by exchanging the various cable with the single cable RF signal will have increased energy and this will increase the amplitude as well.