Why can Prometheus not simply take the place of Instana's tracing?
Select an answer to reveal the explanation.
Short Explanation
Prometheus gives you aggregated metrics, not per-request traces. You need traces to see how one call moved through services and caused an error.
Full Explanation
Prometheus is built around time-series metrics: counters and gauges aggregated over time. Distributed tracing follows an individual request across service boundaries, which is a fundamentally different data model and the basis of Instana's root-cause analysis. The option stating that Prometheus captures traces but retains them for too short a period is incorrect because retention is not the issue; the trace data is not collected in the first place. The option saying Prometheus traces cannot be exported to any external system is incorrect for the same reason; there is nothing to export. The option claiming Prometheus captures traces only for applications written in supported languages is incorrect because language support governs tracing instrumentation generally and is not what distinguishes Prometheus here. For the exam, keep metrics and traces distinct and know which system provides which.