If you're already getting and A in the class, I guarantee there is no way in hell you'll fail these "exit exams", unless you cheated on everything else. Do your studying and make sure you understand the material, and you won't have anything to worry about. In my area, you can usually find online pdf versions of provincial exams from previous years, basically telling you everything you need to know.
Anyone who did their shit properly will pass a test like that with ease. The questions will always be more simple than that of a unit/chapter test given out to you by your teacher.