The usual symptoms of inadequate negative tests are the ones that indicate that the code is not handling the possible errors or exceptions that may occur in different scenarios. For example, when an Apex batch job runs at a scheduled time, an increased number of Apex execution errors occur over all1, this means that the code is not handling the possible concurrency issues, governor limits, or data quality issues that may arise when the job runs. Similarly, when an Apex process runs into an un-handled exception when an HTTP callout has an unexpected status code in the response body1, this means that the code is not handling the possible network issues, authentication issues, or API errors that may occur when making the callout. Another symptom is when developers constantly ask the testers for a screenshot of the error and the exact steps of reproducing the error1, this means that the code is not logging the error details or providing meaningful error messages to the users. Option A is incorrect because turning to the debug log for details of the failed Apex executions is not a symptom of inadequate negative tests, but a normal practice of debugging the code. Option E is incorrect because the delivered user interfaces are not meeting the expectations of the business users is not a symptom of inadequate negative tests, but a symptom of poor user interface design or incomplete requirements.