Which of the following is NOT a type of rapid prototyping?

Freeze drying is indeed not classified as a type of rapid prototyping. Rapid prototyping refers to a range of techniques used to quickly fabricate a scale model or a part using three-dimensional computer-aided design (CAD) data. This process is essential in tissue engineering as it allows for the rapid creation of scaffolds that can support cellular growth and tissue development.

On the other hand, stereolithography, 3D printing, and precision extruding deposition are all methodologies that directly fall under the umbrella of rapid prototyping. Stereolithography utilizes a laser to cure polymer resins layer by layer, 3D printing involves additive manufacturing techniques to create structures by adding material in layers, and precision extruding deposition focuses on expelling materials in a precise manner to build 3D shapes. All of these methods enable quick and efficient production, aligning closely with the needs of research and development in fields like tissue engineering.