Most countries rely upon the police to enforce the law. Police officers most often must be professionally trained in law enforcement before they are permitted to act under the 'migith of law', to issue legal warnings and citations, execute search or other legal warrants and to make arrests.
colour
Tenet: any opinion, principle, doctrine, dogma, etc., especially one held as true by members of a profession, group, or movement.
Hence, from these two options which come close, option (c) is a better choice.