1. The forks shown are made of silver (Ag). Some of the silver forks shown have lost their luster—they have become tarnished. This is an
example of Type here.

Corrosion

Explanation:

Silver, although known as a nobble metal, is also subject to corrosion process such as having silver tarnish when exposed to sulfur and air.

Tarnishing occurs on the surfaces of some metals such as brass, copper, and silver, which results in a corroded layer. Silver tarnish occurs from the chemical reaction that takes place when silver is exposed to sulfur which results in the formation of black Ag₂S

In order to restore the original silver surface, the silver tarnish (silver sulfide) layer is removed.

We have the statement presented here as follows;

The forks shown are made of silver (Ag). Some of the silver forks shown have lost their luster - they have become tarnished. This is an example of Corrosion.