Ais any device connected to a network such as a computer, printer, or game console.

Node

Explanation:

Other examples of nodes include servers, personal computers, hubs switches, modems, and etcetera. These devices must be connected together in a  network such as an Ethernet or WiFi. These nodes are given addresses depending on the communications layer they operate on the network.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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