When operating in workspace mode on FortiManager 7.4, the administrator must understand how object references and deletions work:

Option C- "FortiManager will not allow the administrator to delete a referenced address object until they lock the ADOM":In workspace mode, all changes are managed within an Administrative Domain (ADOM) scope. When an object (like an address object) is referenced in a policy, FortiManager prevents its deletion to maintain configuration integrity. The ADOM must be locked by the administrator to make changes to any referenced objects. This locking mechanism ensures that no unintended deletions or changes occur that could disrupt the policies or configuration.

FortiManager Reference: "In workspace mode, changes to objects or policies require the ADOM to be locked. If an object is referenced, you must lock the ADOM before deleting or modifying the object." (FortiManager 7.4 Administration Guide, Section on Workspace Mode and ADOM Management)

Option D- "FortiManager will replace the deleted address object with the none address object in the referenced firewall policy":If the administrator attempts to delete an address object that is currently referenced by a firewall policy, FortiManager will replace the deleted object with the 'none' address object. This is done to maintain the policy structure and avoid policy corruption due to a missing reference. This behavior ensures that the firewall policy remains syntactically correct, even though the specific address object is no longer in use.

FortiManager Reference: "When a referenced object is deleted, FortiManager will replace it with a 'none' object in the policy. This behavior is to ensure the integrity and continuity of the policy configurations." (FortiManager 7.4 Administration Guide, Object Management and Policy Handling in Workspace Mode)