To create trusted images, the user must be able to push images and sign them. AcrPush allows pushing image content to the registry, while AcrImageSigner allows signing trusted images. Contributor would be excessive because it grants broad management rights. Quarantine reader/writer roles relate to quarantine workflows, not content trust signing. The combination of AcrPush and AcrImageSigner matches least privilege for trusted image creation. This answer also follows operational scalability. Microsoft security architecture favors policy-driven deployment, agentless assessment, managed identities, and Defender workload plans where possible. Those mechanisms reduce manual configuration while keeping enforcement tied to the resource type, which is why the selected choice is stronger than manual or after-the-fact alternatives. 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 > Azure Container Registry security; Microsoft Learn > ACR roles for push and image signing.

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