You work for a large bank where your main application is a payment processing gateway API. You deployed the application on Oracle Container Engine for Kubernetes (OKE) and used API Gateway with several policies to control the access of the API endpoint. However, your customers are complaining about the unavailability of the API endpoint. Upon checking, you noticed that the Gateway URL is throwing Service Unavailable error. You need to check the backend latency and backend responses when this error started last night. What should you do to get this data? (Choose the best answer.) 

Answer options:

A. Check with the application owner and search the log file for the container to get the metrics from the log file.
B. Go to Governance Menu and click on Audit to see the Audit log for the API Gateway. Filter it using Start and End date with a 503 response status.
C. Go to Developer Services and click on API Gateway. Go to the detail page of the gateway and select Metrics. Change the Start and End time to filter the metrics.
D. Go to Monitoring and click on Service Metrics. Choose the Metric Namespace as oci_apigateway. Change the Start and End time accordingly. Add a Dimension and select httpStatusCode: 503. Check the backend latency and backend responses metric.

D

Reference: https://docs.cloud.oracle.com/en-us/iaas/Content/APIGateway/Reference/apigatewaymetrics.htm