You have an Azure subscription named Sub1 that contains a storage account named storage1.

Defender for Storage malware scanning publishes scan result events that can be consumed by automation services. Azure Event Grid is the native event routing mechanism for storage and Defender for Storage scan outcomes, so it is the right trigger for remediation such as quarantine, delete, notification, or workflow invocation. Application Insights observes application telemetry, Event Hubs is mainly a streaming pipeline, and Azure Policy governs configuration compliance rather than reacting to individual malicious-file detections. For this domain, least privilege means granting only the required data operation or allowing only the required network flow. The correct response avoids shared keys, broad peering, general contributor roles, or log-only controls when the scenario demands prevention, routing, event triggering, or account-specific configuration. The result is a direct exam-style implementation choice: it changes the required security behavior without relying on unrelated monitoring, manual cleanup, or excessive privilege. Official Microsoft source/topic: SC-500 Study Guide > Defender for Storage threat protection; Microsoft Learn > Malware scanning in Defender for Storage events.

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