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Why is coke used to remove oxygen from metal oxide ores?

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A color-coded periodic table of the elements displays each element's symbol and atomic number, with categories such as alkali metals, noble gases, halogens, transition metals, and actinoid elements distinguished by different background colors. — carbon group element Modern version of the periodic table of the elements (printable).

Coke is used to remove oxygen from metal oxide ores because it acts as a high-temperature reducing agent in metallurgical processing.1

During the smelting process, the metal oxide is heated to high temperatures in the presence of coke, which is composed chiefly of carbon. The carbon in the fuel reacts with the oxygen combined with the metal, causing the oxygen to be stripped away and released as carbon monoxide or carbon dioxide. This chemical reaction effectively frees the metal from its ore.231

Beyond its role in chemical reduction, coke serves as a vital fuel source to achieve the high temperatures necessary for these reactions to occur within furnaces.23