Correct Option: D

Anodizing is an electrochemical process that converts the metal surface into a decorative, durable, corrosion-resistant, anodic oxide finish. Aluminum is ideally suited to anodizing, although other nonferrous metals, such as magnesium and titanium, also can be anodized. Galvanization is the process of applying a protective zinc coating to steel or iron, to prevent rusting. Galvanizing protects in two ways :
⚈ It forms a coating of corrosion-resistant zinc which prevents corrosive substances from reaching the more delicate part of the metal
⚈ The zinc serves as a sacrificial anode so that even if the coating is scratched, the exposed steel will still be protected by the remaining zinc.
Vitreous enamel also known as porcelain enamel, is a type of glass coating. It is typically bonded to a metal or another enamel, then fired at around 850 degrees Fahrenheit (454 Celsius). Coating metal with vitreous enamel can prevent it from corroding, add a decorative flair and make it easier to clean. The inorganic coating provides resistance to abrasion and wear, making it a practical technology for cooking utensils and cookware, as well as jewelry and decorative accessories.
Powder coating is a type of coating that is applied as a free-flowing, dry powder. The main difference between a conventional liquid paint and a powder coating is that the powder coating does not require a solvent to keep the binder and filler parts in a liquid suspension form. The coating is typically applied electrostatically and is then cured under heat to allow it to flow and form a "skin". The powder may be a thermoplastic or a thermosetpolymer.