Which principle explains the artifacts left behind after changes to a hard disk?

Locard's Exchange Principle is the correct choice because it posits that whenever a person comes into contact with an environment, there is a transfer of material between them. This principle is particularly relevant in forensic science and investigations, as it underscores the idea that every action creates a trace or artifact that evidence can reveal about the interaction. In the context of a hard disk, changes made to the disk—whether through data deletion, modification, or other actions—leave behind traces or artifacts. These remnants can often be recovered and analyzed, providing insight into the previous state of the disk and the activities that occurred.

The other options do not relate directly to the concept of artifacts on a hard disk. For example, the CSI Effect refers to the influence of crime shows on public perceptions of forensic science but does not explain how evidence is left behind. The Butterfly Effect relates to chaos theory and how small changes can have vast consequences, while Moore's Law pertains to the exponential growth of computing power over time, not the preservation of artifacts or evidence from interactions.