What does the term "corpus delicti" signify in criminal law?

The term "corpus delicti" is a fundamental principle in criminal law that translates to "body of the crime." It signifies that, in order to secure a conviction, the prosecution must establish that a crime has indeed occurred. This means presenting evidence that shows the essential elements of a crime—such as the occurrence of a prohibited act and the connection to the defendant. The concept ensures that an individual cannot be convicted solely based on confessions or accusations; there must be concrete evidence demonstrating that the crime took place.

In the context of the other options, while they relate to aspects of criminal investigations, they do not encapsulate the legal requirement that a crime must be substantiated by evidence before a conviction can be attained. Physical evidence of a crime scene, methods of operation of a suspect, and the identification of witnesses are all important components of the investigation and prosecution process, but they do not define the principle of "corpus delicti." The focus here is strictly on the necessity of demonstrating that a crime occurred, which is the essence of the correct answer.