What is the definition of a 'delinquent minor'?

A 'delinquent minor' refers specifically to a minor who has engaged in behavior that violates the law. In this context, it is crucial to focus on the distinction between general age definitions and behavior-based definitions. The correct definition highlights that a delinquent minor is someone who has broken a law prior to reaching the age of 18. This identification is grounded in legal terminology where actions that contravene established laws qualify the individual as 'delinquent,' making this choice the most accurate in the context of law enforcement and juvenile justice.

The other choices present broader categories that do not capture the specific legal focus of delinquency. A minor under the age of 21 does not necessarily imply any unlawful behavior, and could include individuals who are compliant with the law. Medical care needs and neglect by guardians touch on important social issues but are not directly reflective of delinquency since they do not involve a minor's legal infractions. Thus, the definition accurately encapsulates the essence of a delinquent minor as someone whose actions have led them into conflict with legal statutes.