TAE recommends controlled change management to isolate causes when multiple changes are introduced. When you apply more than one change at once, diagnosing failures becomes harder because you cannot easily attribute effects to a specific change. The best practice is to implement changes incrementally, validating automation and system behavior after each change using a representative subset of tests (e.g., smoke/build verification or targeted regression) to quickly detect issues. Because the system is business-critical, risk mitigation is stronger: you want early detection and clear attribution. After each change is validated with a subset, you then execute the full updated regression suite to ensure overall coverage and confidence. Options A and C apply two changes before running tests, which reduces diagnostic clarity and increases the risk of late discovery. Option D describes incremental changes with subset testing but omits the final full-suite run, which TAE would recommend to ensure broad coverage after all changes have been applied. Therefore, the best sequence is: change one item, run a subset, repeat for the next change, then run all updated scripts.

TAE describes contract testing as verifying that two parties (e.g., consumer and provider services) adhere to an agreed interface contract, enabling earlier, more targeted detection of integration mismatches without requiring full end-to-end integration in every test run. A key distinction in approaches is indeed who defines/publishes the contract. In provider-driven contracts, the provider defines the contract describing what it offers; consumers validate compatibility against it. In consumer-driven contract testing, consumers define expectations (often per consumer), and providers verify they satisfy those expectations. Option A is false because stubs/mocks (or simulated counterparts) are frequently used to allow each side to test independently and deterministically, which is one of contract testing’s practical strengths. Option B is too narrow: contract testing can apply beyond REST (e.g., GraphQL, gRPC, messaging/event contracts). Option D is also too restrictive: it can apply to asynchronous interactions (events/messages) as well as synchronous calls. Therefore, the accurate statement is option C

TAE describes “intrusiveness” as the degree to which automation reaches into internal implementation details of the SUT rather than interacting through externally visible, user-realistic interfaces. Using browser drivers and browser automation APIs exercises the UI similarly to a real user (via the browser’s supported automation hooks), which is generally less intrusive than directly manipulating the DOM and internal JavaScript. Direct DOM/JS access can bypass real user interaction pathways, skip browser event chains, and depend on internal structures that are not part of the stable external contract. This increases the risk of false positives: tests may “pass” by forcing UI states or reading internal values even when the application would not behave correctly for real users. Less intrusive automation (through browser-level drivers) tends to provide higher confidence that observed behavior reflects real user experience, reducing the chance that tests succeed while user-visible behavior is broken. TAE therefore associates lower intrusion with stronger validity of results and lower false-positive risk, especially for system/UI-level validation. While browser-driven automation can still be flaky for other reasons (timing, environment), in the specific comparison of interaction method, browser-driver-based execution is the less intrusive option and is less likely to create false positives than direct internal DOM/JS manipulation.