Choose Admin1 because the planned Defender for Cloud change is to enable the NIST SP 800-53 Rev. 5 regulatory compliance standard for Sub1. Defender for Cloud implements regulatory compliance standards through Azure Policy initiatives, and assigning a new standard requires permissions to create or manage policy assignments.

Microsoft states that assigning a regulatory compliance standard requires Owner or Policy Contributor permissions at the relevant scope. Microsoft Learn Admin1 has the Resource Policy Contributor Azure role on Sub1, which provides the policy-management permissions required to assign policy initiatives and therefore supports enabling the NIST standard without granting broader resource-management permissions.

Admin2 has User Access Administrator, which manages Azure RBAC assignments but does not provide the policy-management permissions required for this operation. Admin3 has Contributor, which can manage Azure resources but is restricted from performing certain Microsoft.Authorization operations, including policy assignment operations needed here. Admin4 is a Global Administrator in Microsoft Entra but has no Azure role assignment for Sub1; Microsoft Entra directory administration does not automatically provide subscription-level Defender for Cloud policy-management rights.

Because Admin1 already has the specific policy-management role required for the change, selecting Admin1 satisfies both the functional requirement and the principle of least privilege.

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