Final answer:
The technique called Freeze-fracture involves fracturing a frozen specimen by striking it with a knife-edge to study internal structures like cell membranes. The correct option is c.
Step-by-step explanation:
The electron microscope technique that involves striking a frozen specimen with a knife-edge, resulting in the ice of the tissue block cracking in a way that interacts with the tissue, is known as Freeze-fracture.
During the freeze-fracture process, the frozen specimen is fractured, which allows the study of structures such as cell membranes that are split along their middle by this technique.
This method differs from other techniques such as plastic section positive staining and whole-mount negative staining, which involve embedding and staining procedures, or shadow casting that deals with coating the surface of the specimen to reveal its three-dimensional shape. The correct option is c.