Final answer:
OCI Notifications is the OCI Monitoring service feature that uses metrics for monitoring and consists of a trigger action and notification method.
Step-by-step explanation:
The OCI Monitoring service feature that uses metrics for monitoring and consists of a trigger action and notification method is OCI Notifications. This service allows you to set up rules that monitor specific metrics and trigger notifications based on defined thresholds.
For example, you can set up a rule to monitor the CPU utilization of an instance. If the CPU utilization exceeds a certain threshold, a trigger action can be triggered, such as sending an email notification to specified recipients.
OCI Notifications helps you proactively monitor and respond to critical events and performance issues, ensuring the smooth operation of your Oracle Cloud Infrastructure resources.