Correct Option: D

Wrought iron or malleable iron is the purest form of commercial iron as it contains the lowest percentage of carbon (0.12-0.25%) and impurities of S, P, Mn and Si in minute amount (about 0.3%). It is made by melting cast iron with scrap iron in a reverberatory furnace lined with Fe2O3 which oxidizes C, Si, P, etc, most of which are then removed by rolling.