The requirement follows a direct manager-to-subordinate relationship, so the role hierarchy is the native record-access mechanism. By placing the operations users below the operations manager and enabling Grant Access Using Hierarchies for the custom Scheduled Course object, Salesforce can automatically provide the manager access to records owned by those subordinate users. The manager must also have the necessary object-level Edit permission because hierarchy access cannot create object capability that the user lacks. A public group alone does not share records; it is simply a reusable collection that must be referenced by another sharing mechanism. An ownership-based sharing rule could create access, but it would duplicate a relationship already expressed by the hierarchy and add unnecessary maintenance across hundreds of regions. Study Guide reference: Access to Records - Role Hierarchy, Grant Access Using Hierarchies, custom-object sharing, manager access, and object permissions. The implementation should also be validated with representative users so effective permissions, sharing inheritance, and any cross-object access behave exactly as designed before production release.