PCA (Prometheus Certified Associate) sample exam question with answer 579

Question:
Which type of observability data is BEST represented by the following description?
Service A called service B which in turn called services C and D. While service C responded successfully, service D returned a 503 HTTP error. The entire interaction took 1.2 seconds.

1. Trace
2. Event
3. Metric
4. Log

Answer:
A - is the correct answer
B - is incorrect as the given description represents at least several events. Moreover, the description details a transaction flow through multiple services which most closely aligns with the concept of a trace
C - is incorrect as a metric is a numeric measurement and this description contains multiple measurements. Moreover, the description details a transaction flow through multiple services which most closely aligns with the concept of a trace
D - is incorrect. Since logs are textual data, this description could technically represent a log. However, the description details a transaction flow through multiple services which most closely aligns with the concept of a trace