Which alloy is formed from copper and zinc and is commonly used for EDM wire?

Brass is the correct answer because it is an alloy primarily made from copper and zinc. In the context of Electrical Discharge Machining (EDM), brass is often chosen for wire due to its excellent electrical conductivity and good machinability, making it ideal for precision cutting applications. The specific combination of copper and zinc in brass contributes to its desirable properties, including strength and resistance to corrosion, which are beneficial during the EDM process.

Aluminum, bronze, and steel do not fit the description. Aluminum is a separate metal that doesn't typically form a significant alloy with zinc in this context. Bronze is primarily an alloy of copper and tin, though it can contain other elements as well, but it is not the specific alloy produced from copper and zinc. Steel is an alloy of iron and carbon, which does not include copper or zinc as a primary component.