You have a container in an Azure Cosmos DB for NoSQL account. You need to create an alert based on a custom Log Analytics query. Which signal type should you use?

When creating an alert rule in Azure Monitor based on the results of a custom Log Analytics query, you must choose 'Log' as the signal type. This signal type allows you to specify a Kusto Query Language (KQL) query against your Log Analytics workspace data to define the alert condition.

Metrics signal type is used for alerts based on numeric values collected at regular intervals, such as RU consumption or latency, rather than custom query results from logs.

Activity Log signal type is used for alerts based on events in the Azure Activity Log, such as administrative operations or service health events, not custom log data.

Resource Health signal type is used for alerts related to the health of an Azure resource, indicating service availability issues, and does not support custom Log Analytics queries.