Answer:
B: a type of coaxial cable.
Explanation:
Thicknet is a type of network coaxial cable normally used for networking purpose of standard Ethernet.Coaxial cables are insulated copper cable used to block interference. Thciknet cable can support transmission speeds of upto 10 Mbps over range of 500 meters. It has 3/8 inch diameter and 50 ohm impedance.
Impedance is the effective resistance of the wire or circuit when current is passing through it.