Which of the following metrics would be MOST useful to monitor during test execution?

Which one of the following answers describes a test condition?

Which of the following statements is a valid objective for testing?

Which of the following statements correctly describes the difference between testing and debugging?

Which one of the statements below describes the most common situation for a failure discovered during testing or in production?

Mr. Test has been testing software applications on mobile devices for a period of 5 years. He has a wealth of experience in testing mobile applications and achieves better results in a shorter time than others. Over several months Mr. Test did not modify the existing automated test cases and did not create any new test cases. This leads to fewer and fewer defects being found by executing the tests. What principle of testing did Mr. Test not observe?