Option C correctly addresses the requirement for showing the same maintenance page across multiple locales by having each different domain alias ('nto.eu', 'nto.at', 'nto.de') mapped to the same www domain ('www.nto.eu'). This setup allows all traffic, regardless of the original locale-specific domain, to be directed to a single, unified maintenance page hosted under the 'www.nto.eu' domain. This ensures consistency in the maintenance message presented to all users, irrespective of their regional domain.