You need to monitor, troubleshoot, and improve application performance in a complex microservices architecture. Which GCP service should you primarily consider for distributed tracing and monitoring?

*Explanation:* To effectively monitor, troubleshoot, and improve application performance in a complex microservices architecture, you should primarily consider **Cloud Trace**. Cloud Trace is specifically designed for distributed tracing, allowing you to trace and analyze requests as they flow through various services in your architecture. It provides valuable insights into the performance of your microservices, helping you identify bottlenecks, troubleshoot issues, and optimize your application's performance. While other services like Cloud Debugger, Cloud Monitoring, Cloud Profiler, and Stackdriver Logging offer useful capabilities, they are not specialized for distributed tracing and may not provide the detailed insights needed for microservices performance optimization.