You need to produce a monthly report summarizing all new Azure Resource Manager (ARM) resource deployments in a subscription. Which source should you query to obtain deployment events and details?

The Azure Activity Log records all control-plane events in an Azure subscription, including resource deployments, updates, and deletions. This makes it the ideal source for tracking new Azure Resource Manager (ARM) deployments for reporting purposes. You can query the Activity Log to filter for specific event types, such as Microsoft.Resources/deployments/write, to get the details of new deployments. Azure Monitor action groups are used for notifications and automation based on alerts, not for querying historical event data. Azure Arc extends Azure management to on-premises and other cloud environments; it doesn't provide a log of Azure-native deployments. Azure Monitor metrics collect numerical data about resource performance and availability, not administrative operations like resource deployments.