Which of the following best describes reasonable suspicion?

Reasonable suspicion is an important legal standard that is less stringent than probable cause. It requires that law enforcement officers have specific and articulable facts that lead them to suspect that a crime may be occurring or about to occur. This standard allows officers to engage in brief stops and detentions of individuals when they observe behavior that raises a reasonable suspicion of criminal activity, without needing the more substantial evidence required for probable cause.

In contrast to the other options, a determination of reasonable suspicion does not require a belief based solely on vague or unfounded concerns; it must be supported by specific facts. Additionally, reasonable suspicion is not equivalent to the needs for a search warrant, which requires probable cause backed by substantial evidence. Therefore, the definition of reasonable suspicion aligns closely with the notion of it being "something less than probable cause," as it represents a lower threshold for action by law enforcement when encountering potential criminal behavior.