John recently purchased a High Definition plasma television and needed to have it installed. The installers told John that for the best picture quality he should use cables with an all-copper core, rubber insulation, and 24k gold contacts. The electrical signal travels down the copper portion of the cable while the rubber insulates the cable from a loss of electrical current and heat. Which physical property explains the difference in ability of copper and rubber to transmit electricity?
ductility
density
conductivity