The correct answer is Create a new Microsoft Defender for Endpoint workspace in Europe.

Data residency for Microsoft Defender for Endpoint is determined by the workspace location and not by client side settings. Creating a workspace that is provisioned in Europe ensures that new telemetry and logs are stored in European datacenters and meets the GDPR requirement for regional storage.

Delete the existing United States workspace is incorrect because deleting the workspace does not move telemetry to Europe and could cause loss of historical data. Deletion alone does not reconfigure endpoints to send data to a European location.

Use Google Cloud Storage location controls to redirect telemetry to Europe is incorrect because Google Cloud Storage is not part of Microsoft Defender for Endpoint telemetry routing. Defender for Endpoint telemetry is handled by Microsoft services and cannot be redirected using Google Cloud controls.

Offboard endpoints from the current workspace and then enroll them into a European workspace is incorrect as stated in the options for this question. The essential step to satisfy data residency is to have a workspace that is provisioned in Europe. Offboarding and re-enrolling devices is an operational task that follows creating the European workspace but the question asks which step ensures data residency and that step is creating the European workspace.

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