You're responsible for setting up a CI/CD pipeline for a new project. You also need to ensure traceability for compliance requirements. The application is hosted on GKE and utilizes multiple microservices. Which GCP services would best serve these needs?

Cloud Build is a fully managed CI/CD platform that can automate the build, test, and deployment of applications, including those on GKE. It integrates well with source control and provides detailed build logs, crucial for traceability. Cloud Monitoring (part of Operations) collects metrics, logs, and events from GCP services, including Cloud Build, providing the necessary visibility and audit trails for compliance. Cloud Source Repositories is a source control service, but it doesn't directly provide CI/CD or monitoring. Stackdriver is the old name for Google Cloud's operations suite, which includes Cloud Monitoring, but the option is less precise. Kubernetes Engine hosts the application but isn't a CI/CD or monitoring tool itself. Cloud Endpoints manages APIs. App Engine is a platform for serverless applications, not directly related to CI/CD for GKE or monitoring for compliance. Cloud Trace is for distributed tracing, which is useful for debugging but not the primary tool for overall CI/CD and compliance traceability.