Price is a major consideration!
I guess you mean wiring. The answer is because it's cheaper.
Silver is, then copper, then gold, and then aluminum. Copper is used for wiring because it is cheaper than silver. Aluminum is not used very much anymore because it can be dangerous when installed improperly.
Out of copper, silver, and gold, silver has the highest conductivity.
Some metals that are not silver gray in color include gold (yellow), copper (orange-red), brass (yellow-brown), and bronze (reddish-brown).
Copper
Not a meaningful question. Gold coins were made from gold and copper without any silver in them. Silver coins were made from silver and copper without any gold.
Copper, silver, and gold are three good conductors of electricity due to their low resistivity and high conductivity properties. These elements are commonly used in electrical wiring and electronic components for efficient transmission of electricity.
Gold, Silver and Copper belong to the native elements mineral group.
Gold
It isn't, gold(Au) , silver(Ag) and copper(Cu) are all separate elements. But if you're talking about when they add copper or silver to gold, it's to harden it, so you can't bend it in your hands.
Silver is harder than gold but softer than copper.
Gold follows copper and silver in order, in the same vertical column in the periodic table of the elements.