Consider the following forms of iron: I. Pig iron II. Wrought iron IIL Cast iron What is the sequence of these in terms of descending order of their carbon content?

The carbon content in different forms of iron determines their properties and classification. Pig iron is the immediate product of smelting iron ore in a blast furnace and contains the highest carbon content, typically ranging from 3.8% to 4.7% [t9]. Cast iron is produced by refining pig iron and generally contains between 2% and 4% carbon [t6][t7]. In contrast, wrought iron is considered the purest form of commercial iron, containing very minute amounts of carbon, typically less than 0.08% [t3][t6]. Therefore, the descending order of carbon content is Pig iron (I), followed by Cast iron (III), and finally Wrought iron (II). This sequence (I, III, II) reflects the transition from the crude furnace product to the highly refined malleable form used in traditional blacksmithing.