Elements in the group of noble gases typically fail to chemically react with other elements. This is true because noble gases tend to have —

a single valence electron in its outer shell.

a full outer shell of valence electrons.

fewer neutrons than other elements.

more protons than other elements.

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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