The correct option is A True
Cast Iron is the most impure form of iron and contains the highest percentage of carbon from 2.5 to 5 percent and about 2 percent of other impurities like Si, P, Mn and S. Wrought Iron is the purest form of iron. It contains the lowest percentage of carbon 0.1 to 0.25% and 0.35 other impurities. It is manufactured from cast iron by pudding process.