The correct option is SODIUM, Na.
Out of all the options given above, it is only sodium that is a metal, the other ones are non metals and metalloid. Generally, metals are good conductor of heat and electricity because they have electrons, which are able to move about and thus they are thus able to conduct electricity round a circuit. Metals are generally bonded together by strong metallic bonds so they have high melting and boiling points, which make them suitable as conductors.
