Coke is utilised in the production of which of the following?

Coke is a greyish-black, hard, porous solid obtained by the destructive distillation of coal. It is high in carbon and used as a fuel and reducing agent in furnaces during industrial manufacturing processes. Since burning coke produces very little smoke, it is sometimes preferred over coal. 

Blast Furnace is a metallurgical furnace in which preheated air is blown from the bottom during the extraction of metals like iron from its ores. The fuel contains a mixture of flux (limestone) and coke and is supplied and pumped through the top of the furnace. This generates heat and carbon monoxide gas, which is used to reduce the iron ore to iron. The iron is then melted and poured into moulds to form pig iron, which is then processed further to produce steel.