Which of the following best describes a thermoplastic?

A thermoplastic is defined as a type of material that can be reshaped when heat is applied. This characteristic is significant because it allows for various processes, such as molding and extrusion, which are essential in manufacturing. When heated, thermoplastics soften and become pliable, making it possible to mold them into different shapes. Once cooled, they harden and retain their new shape, but they can again be reheated and reshaped without undergoing any chemical change.

This property of being reprocessable with heat distinguishes thermoplastics from thermosetting plastics, which permanently harden after curing and cannot be reshaped. The ability to repeatedly reshape thermoplastics contributes to their popularity in a wide range of applications, including packaging, automotive parts, and consumer goods. Other choices do not accurately define thermoplastics and may describe properties of other materials. For instance, the first option pertains to thermosets, while the third option incorrectly suggests a limitation on recycling that does not apply to all thermoplastics. The fourth choice describing a type of rubber compound is unrelated to the properties of thermoplastics.