What distinguishes a search from an investigatory stop?

A search is characterized by its intrusive nature, as it involves entering a person's private space or examining their belongings with the intent of finding evidence of a crime. This level of intrusion necessitates a higher legal standard, typically a warrant, consent, or probable cause depending on the circumstances.

In contrast, an investigatory stop, often referred to as a Terry stop, allows law enforcement to temporarily detain an individual based on reasonable suspicion that the person is involved in criminal activity. This does not involve a search of the individual’s private space, but rather a brief encounter to confirm or dispel the officers' suspicions without intruding into personal privacy to the extent a search would.

Thus, the nature of a search's intrusion into personal space is what distinctly separates it from an investigatory stop, making option A the correct choice.