To clarify the meaning here, rather than just pointing out the exception - a lot of multi choice answers will attempt to throw you off if you don’t know the answer 100% by specifying that something that is sometimes true is always true, or that all cases of something are true, for instance. All of the above isn’t referring to all cases of a particular scenario, it instead refers to all other answers listed for the question - in that case, examiners would usually only think to use that format if they’ve made that the correct answer (or at least often enough to give you an advantage picking that).
I’ll add an extra tip as well - these rules don’t apply in classes about statistics, probabilities or other fields where guessing is part of the training - I have heard of statistics classes mentioning the fun fact that ‘c’ is the most common correct answer in multi choice (this likely varies by study and/or region) and then gave multi choice tests with literally no ‘c’ answers being correct.
