Which of the following describes a thermosetting coating?

A thermosetting coating is characterized by its ability to undergo a chemical change when it is cured, which causes it to harden permanently. Once the curing process occurs, thermosetting coatings cannot be remelted or reshaped; they become inflexible and maintain their form. This property results from the cross-linking of polymer chains during the curing process, which creates a three-dimensional network that provides durability and resistance to heat and chemicals.

In contrast, other options describe characteristics not typical of thermosetting coatings. For instance, the ability to be remelted or reshaped represents thermoplastic materials, while the notion of being easily removable is not a trait associated with thermosetting coatings, as their purpose is to provide a durable and long-lasting finish. Additionally, remaining flexible after curing aligns more with certain thermoplastics or elastomers rather than with thermosetting materials, which become rigid after the curing phase. Therefore, the defining characteristic of thermosetting coatings is their permanent hardening upon curing, which is clearly captured in the correct choice.