Identify the conceptual definition that most accurately encapsulates the term 'State' as utilized within political and constitutional jurisprudence:
1. An administrative apparatus whose sole defining characteristic is the promotion of socio-economic well-being and wealth redistribution among its citizenry.
2. A bureaucratic institution designed exclusively to exercise independent executive and legislative functions, synonymous with the reigning administration.
3. A comprehensive political institution representing a sovereign populace that permanently occupies and administers a geographically defined territory.