The iron obtained from the blast furnace is known as:

Correct answer: (b) Pig iron

Explanation

The iron that comes out of a blast furnace is called pig iron. It has about 4% carbon and other impurities, so it is hard but brittle.

• Cast iron is made by remelting pig iron with scrap iron and coke; it has about 3% carbon.
• Wrought iron is the purest form, with less than 0.2% carbon.
• Steel has a controlled amount of carbon (about 0.1–1.5%), sometimes with other metals.