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Galvanization involves coating iron or steel with a protective layer of zinc to prevent rusting.
Option 1 is incorrect as lead is not typically used for galvanization. Even though it is corrosion-resistant, it`s toxic and not used to coat iron or steel.
Option 2 presents chromium, which indeed forms a protective barrier when used to coat iron or steel, but the process is called `chroming` rather than galvanization. Chromium provides a shiny, attractive surface and is often seen on vehicle parts, tools, and kitchen appliances.
Option 3 is the correct answer. In the galvanization process, a layer of zinc is applied to the surface of iron or steel. This zinc layer not only forms a barrier against corrosion factors but also sacrifices itself (through a process known as `sacrificial protection`) by rusting before the iron or the steel does.
Option 4 is incorrect as tin is used in a different protective process called tinning. Tinned iron or steel is primarily used for making cans and other food storage containers because it`s food-grade safe, but it`s not galvanized.