The correct answer is Create an Activity Log alert in Azure Monitor for the Create or Update Container Registry operation and attach an action group that sends an email.

An Activity Log alert watches management plane events for the subscription and can be filtered to the specific Create or Update operation for Container Registry. You attach a action group to that alert to deliver an email to the team without needing custom polling or glue code.

Set up an Event Grid subscription on the subscription scope filtered to Microsoft.ContainerRegistry registries and invoke an Azure Function is not correct because that approach is focused on event routing and would still require custom code to convert events into an email. The built in Activity Log alert plus an action group is the straightforward supported path to notify on ARM create operations.

Deploy an Azure Automation Runbook that polls the subscription every 10 minutes for new resources and emails the team is not correct because polling is inefficient and introduces latency and operational overhead. Alerts and action groups provide near real time notifications without the need to manage a polling runbook.

Rely on Azure Service Health to watch the tenant and notify when resources are added is not correct because Service Health reports service outages and issues and it does not track or notify on the creation of individual resources in your subscription.

Full AWS Practitioner Certification Question