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Elephants and hyraxes share many anatomical similarities. They both have flat, hoof-like nails on the tips of their toes. They also have four toes on their front feet and three toes on their rear feet. Elephants and hyraxes both develop tusks from their incisor teeth instead of their canine teeth, like most other mammals. In addition to the anatomical similarities, fossil evidence has revealed that hyraxes and elephants share a 40-million-year-old ancestor.

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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