An automation rule is the native Sentinel control for applying actions automatically when incidents are created or updated. It can assign incidents to users or groups, change status/severity, add tags, and run playbooks. This directly matches the requirement to assign all new incidents immediately and flag them for triage. It is more direct than hunting queries and is intended for incident-handling automation. The posture and monitoring objective focuses on turning security data into usable operational outcomes. The correct answer either collects the right signal, grants the right security-operations role, or automates incident handling at the correct layer. Distractors often provide dashboards, queries, or broad permissions, but those do not create the requested workflow or least-privilege security capability. 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 > Sentinel automation rules; Microsoft Learn > automation rule actions for incident assignment.

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