Heat that flows by conduction is the transfer of thermal energy between substances in contact. What must occur for this to happen? The two systems must be the same temperature.
The two systems must not be touching each another.
One system must have higher kinetic energy than the other system.
The thermal energy of one system must be the same as the thermal energy of the other system.

c, liquids evaporate, creating a gas

plasma is the state of matter where the substance is ionized and has no definite shape or volume. the fact of being ionized makes the substance a good electrical conductor.

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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