A small number of API requests to your microservices-based application take a very long time. You know that each request to the API can traverse many services. ...

A small number of API requests to your microservices-based application take a very long time. You know that each request to the API can traverse many services.
You want to know which service takes the longest in those cases.
What should you do?

A. Set timeouts on your application so that you can fail requests faster B. Send custom metrics for each of your requests to Stackdriver Monitoring C. Use Stackdriver Monitoring to look for insights that show when your API latencies are high D. Instrument your application with Stackdriver Trace in order to break down the request latencies at each microservice