The correct answer is D. the Microsoft 365 admin center . Microsoft Learn states that users with a Microsoft 365 Copilot license can use Copilot capabilities, and Microsoft specifically points administrators to the Microsoft 365 admin center and its setup guidance to assign the required licenses to users. Microsoft also documents that the Researcher and Analyst agents were deployed to existing users with Microsoft 365 Copilot licenses and that administrators govern these agents through the Microsoft 365 admin center .

The other portals are not the primary place for this task. Microsoft Entra admin center focuses on identity and access, Microsoft Purview focuses on compliance and governance, and Microsoft Defender focuses on security operations and threat protection. None of those is the main admin experience Microsoft documents for assigning Microsoft 365 Copilot access and managing the availability of Researcher and Analyst. Because the goal is to enable a user to use Microsoft 365 Copilot and its Microsoft-provided agents, the correct administrative tool is the Microsoft 365 admin center .