The cell theory states that all living things are composed of one or more cells that carry out the functions needed to support life. The cell theory also states that ---

New cells arise from existing cells.

Explanation:

According to the cell theory, "all living things are composed of one or more cells; the cell is the basic unit of life; and new cells arise from existing cells"(Lumen Learning).

Cells are the basic unit of life. Some organisms consists of only one cell while other organisms have many cells and are called multicellular organisms.

In multicellular organisms, new cells are formed by the division of preexisting cells.

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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