Solution:Concept- Cast iron is produced from pig iron during the process of obtaining pure iron from ores. These two types of iron are malleable in their less pure forms. Cast and pig iron is derived from different methods.
There is 3-4% about carbon and many impurities in the smaller amount (e.g., S, P, Si, Mn) in iron obtained from blast furnace which is known as pig iron. It can be transformed into a variety of shapes.
Cast iron is different from pig iron and is made by melting pig iron with scrap iron and coke using a hot air blast. It has a slightly lower carbon content (about 1-3% ) and is extremely hard and brittle.
Hence, the correct answer is option 2.