Krista is playing tennis at the park. When the tennis ball flies toward her, Krista hits the ball with her racket, which causes the ball to fly in the opposite direction

2b2t

explanation:

2b2t

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.

if it's not useful, feel free to report for mistake in answer.