Q. In IT networking, which of the following device is used in physical layer?
Answer: Repeater
Notes: In the seven-layer OSI model of computer networking, the physical layer or layer 1 is the first and lowest layer. Devices that operate at the physical layer include repeaters, hubs, network interface cards (NICs), cables and connectors. Repeaters are used to regenerate electrical signals that have attenuated (i.e., weakened) as a result of distance.