PCA (Prometheus Certified Associate) sample exam question with answer 107

Question:
In which of the following scenarios is distributed tracing NOT particularly useful?

1. A monolithic web application
2. A customer interaction with calls that span an internal data center and a public cloud such as AWS
3. A 3-layer web architecture with a frontend, backend and database
4. A batch job that uses an API to make calculations and store the results in a database

Question:
A - is the correct answer. While you can leverage tracing within a single application (denoting various sections of the processing via spans), distributed tracing implies the existence of multiple services involved in handling a transaction.
B - this use case lends itself perfectly to distributed tracing. By tracing transactions from an internal data center to public cloud you can get detailed information on where exactly errors in this larger transaction are occurring.
C - multi-service architectures are the prime use case for distributed tracing.
D - is incorrect as the batch job leverages separate services (an API and a database) to do its work. This use case lends itself nicely to distributed tracing