The correct option is Treat every access attempt as untrusted and authenticate and authorize each request.

This option expresses the core Zero Trust philosophy which says that no user or device is implicitly trusted and that each access attempt must be verified and authorized before access is granted.

Zero Trust emphasizes continuous validation, least privilege access, and making access decisions based on contextual signals for each request. Treating every access attempt as untrusted and authenticating and authorizing each request aligns with those guiding principles and covers both user and device posture as well as network controls.

Require Multi Factor Authentication using Azure AD Conditional Access is incorrect because multi factor authentication and conditional access are useful controls that help implement Zero Trust. They are product specific controls and do not by themselves state the overarching Zero Trust principle.

Use Google Cloud Identity Aware Proxy to gate access to web applications is incorrect because Identity Aware Proxy is a specific Google product that can enforce access controls. It can be part of a Zero Trust implementation but it does not express the fundamental philosophy of treating every access attempt as untrusted.

Mandate that all user accounts are provisioned in Azure Active Directory for access is incorrect because centralizing identities can aid management and security but Zero Trust does not require a particular identity provider. The philosophy focuses on verifying and authorizing each request rather than mandating a single provisioning source.

Full AWS Practitioner Certification Question