To ensure that only valid addresses are entered in the system, you should define the geography validation for country option to Error. This option determines how geography validation is performed when users enter addresses in various applications. If you set this option to Error, then users can only enter addresses that match predefined geographies in the Geography Hierarchy. If users enter invalid addresses, they will receive an error message and will not be able to save the address until they correct it. You do not need to redefine the location structure, as this is a feature that defines how locations are identified and organized in Oracle Fusion Applications. You do not need to redefine the geography hierarchy, as this is a feature that defines how geographies are structured and validated in Oracle Fusion Applications. You do not need to define the geography validation for country option to No Validation, as this option disables geography validation and allows users to enter any address without checking against predefined geographies. Reference: Oracle Financials Cloud: General Ledger 2022 Implementation Professional Objectives - Define Enterprise Structures 12