Microsoft Updated AB-900 Exam Questions and Answers by taron

The correct answer is Microsoft Defender XDR . Microsoft Learn defines Microsoft Defender XDR as a unified pre- and post-breach enterprise defense suite that natively coordinates detection, prevention, investigation, and response across endpoints, identities, email, and applications to provide integrated protection against sophisticated attacks. That wording matches the sentence in the question almost exactly, which makes this the clearly correct choice.

The other options do not fit that definition. Microsoft Entra Conditional Access is Microsoft’s Zero Trust policy engine used to evaluate signals and enforce access policies, not a cross-domain threat detection and response suite. Microsoft Entra ID Protection focuses on detecting and responding to identity risks such as risky sign-ins and risky users. Microsoft Purview is Microsoft’s portfolio for data governance, data security, and compliance. None of those products is described by Microsoft as coordinating detection, prevention, investigation, and response across endpoints, identities, email, and applications in the same integrated XDR manner. Therefore, the only answer that correctly completes the sentence is Microsoft Defender XDR .

The correct selections are No, Yes, Yes . Microsoft documents that the Audit page in the Microsoft Defender portal can be used to search the unified audit log for user and admin actions in the organization. Microsoft also states that audit log search in the Defender portal is the same as audit log search in the Microsoft Purview portal , which means both portals can be used to review administrative actions taken in Microsoft 365.

Microsoft further explains that Microsoft Purview Audit enables organizations to search for audit records of activities that users and admins perform across Microsoft services, making it a correct tool for this requirement.

By contrast, Search & intelligence in the Microsoft 365 admin center is not the feature used to investigate administrator actions through the unified audit log. It is not Microsoft’s documented audit search tool for this purpose. Therefore, for this hotspot the right answers are No for Search & intelligence, Yes for Audit in Microsoft Defender, and Yes for Audit in Microsoft Purview.

The correct answer is C because Microsoft explains that authorization is the process of determining whether an authenticated identity is allowed to access a resource . Microsoft Learn distinguishes authorization from authentication by stating that authentication proves who you are, while authorization decides what you can access or do after identity has been established. In Microsoft 365 and the Microsoft identity platform, authorization commonly involves permissions, scopes, roles, and consent that control access to data and services such as Microsoft Graph, Exchange, SharePoint, or Teams.

Option A is incorrect because it refers more to external identity validation or federation concepts, not authorization itself. Option B describes authentication , not authorization, since it is about verifying identity claims. Option D describes a control such as multifactor authentication or Conditional Access requirements, which can happen before access is granted, but that still is not the definition of authorization. Authorization begins after identity verification and focuses on whether the identity has the right permissions for the requested resource.

The correct answer is D. From the Finance site, configure permissions . Microsoft states that Microsoft 365 Copilot honors existing Microsoft 365 permissions and only grounds responses in content that the signed-in user is already allowed to access. That means if users are getting Finance-site content in Copilot responses, those users likely still have permission to that SharePoint content. The direct fix is to review and correct the site, library, folder, or file permissions on the Finance site so only the intended users retain access.

The other options do not directly solve this requirement. Information Barriers are designed for communication and collaboration segmentation scenarios, not for ordinary site-level oversharing remediation. A Defender data connector is unrelated to SharePoint permission enforcement. Conditional Access controls sign-in and session access conditions, but it does not selectively remove Copilot grounding from one SharePoint site for users who still have site permissions. Because Copilot uses SharePoint and Microsoft Graph permissions as its boundary, the Microsoft-documented corrective action is to fix the Finance site permissions .