ANS:C - sponge iron

The product of a commercial direct reduction process is typically sponge iron. Direct reduction processes are used to convert iron ore into metallic iron without melting the ore. In these processes, iron oxide is reduced by a reducing gas, typically a mixture of carbon monoxide and hydrogen, at elevated temperatures. The result is a spongy mass of metallic iron, which is porous and contains a certain amount of residual impurities, such as carbon, silicon, and other elements. This product is known as sponge iron because of its spongy appearance and relatively high porosity. It can be further processed in various ways, such as compacting it into briquettes or pellets for use in steelmaking processes like the blast furnace or electric arc furnace, where it undergoes further refinement to produce steel.