Reducing App1 Unit and Integration Test Time with Test Impact Analysis

Why the Answer Is Correct

The requirement is to reduce the time spent on unit and integration tests while maintaining the code coverage ratio, so the reduction has to come from running fewer tests rather than from running the same tests faster. Test Impact Analysis does exactly this by analyzing which code changed and automatically selecting only the tests required to validate that change, performing incremental validation of just the affected subset. Because the reduced selection still covers the modified code, the coverage ratio requirement continues to be satisfied, which is what distinguishes this from simply loosening the tests. The vote was unanimous at 100 for C. danisancho gave the technical description, noting that TIA performs incremental validation by automatic test selection and that it automatically selects only the subset of tests required to validate the code being committed.

Why the Other Options Are Wrong

Adding an agent pool (D) increases the agents available to run tests, so the total wall clock time may fall, but the same number of tests still executes and the pipeline now consumes more agent capacity, which is a scaling answer rather than an efficiency answer to a duration problem. Purchasing additional parallel jobs (B) has the same weakness and adds cost, since parallel jobs change concurrency rather than the amount of testing work selected. Enabling flaky test management (A) addresses a different problem entirely, namely identifying and quarantining unreliable tests so they do not consume retries and mask real failures, which helps signal quality but does not reduce the number of tests run for a valid change.

Community Comment Notes

The community was unanimous at 100 for C, and both substance comments identify Test Impact Analysis by name, with danisancho explaining the incremental validation mechanism and marmila confirming the answer. The reasoning is not contested because the question embeds the constraint that makes the answer unique, namely maintaining the coverage ratio, which eliminates every option that merely adds compute. The general pattern is worth carrying forward: when a question asks to reduce test time while keeping a quality bar, the answer is almost always smarter test selection rather than more agents.