4) From the list below, what counts as a disadvantages of 5 GHz Wi-Fi communications?
a) 5 GHz Wi-fi can penetrate walls easily.
b) 5 GHz Wi-Fi is best under LOS and Weak-LOS propagation.
c) 5 GHz Wi-Fi has a large coverage under non-LOS.
d) 5 GHz Wi-Fi has a small path loss.