Outside of modern super-conductors, which metals are primarily used for conductors?

Copper and aluminum are the primary metals used for electrical conductors due to their excellent electrical conductivity and relatively low cost. Copper is particularly favored for its high conductivity, malleability, and resistance to corrosion, making it ideal for a wide range of applications including wiring and circuitry. Aluminum, while not as conductive as copper, is lighter and less expensive, which makes it an attractive alternative for overhead power lines and certain electrical applications.

In contrast, while gold and silver (notably in the first choice) also possess high conductivity, their costs are prohibitive for most standard applications. Iron and brass are less effective as conductors and are typically not used in electrical wiring due to their lower conductivity and susceptibility to corrosion. Lead and zinc, listed in the last option, are also not suitable for electrical conductivity in the same capacity as copper and aluminum. Thus, the selection of copper and aluminum as the primary metals for electrical conductors reflects their balance of performance and cost-effectiveness.