In a creek bed you find smooth rocks of all sizes. What could explain this? A. A chemical change has occurred in these rocks.
B. Water has dissolved the outer layers of rocks.
C. When rocks are transported by water, abrasion occurs as they rub and bump into each other.
D. The types of rocks in streams are not as hard as other rocks.

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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