Easy to say of it would only be used to classify/grade data but because this is a CAPTCHA it somehow has to determine if you answer is “correct” and probably does that by checking if other people agreed with you on the majority of cases and then it gets tricky because one would not only have to take into account if the outline is correct but one thinks that other people would agree with that assessment if you don’t want to get another set of images because the server couldn’t tell of you are a human.