How do we diagram this?

yeah this one is confusing because it expects us to infer "some aren't" from a "most" statement

I am not sure if we would want to diagram this necessarily, but I absolutely want to pay attention to the quantifiers. We know that the majority of artists are less insightful than an average, well educated person. The right answer is just a rephrase of this sentence. To say that most are less insightful is exactly the same as saying that some of the other group are as or more insightful.