Hi dabaum - thanks for the question! Let me see if I can help you out here
The conditional statements in this stimulus establish a few things for us:

1. If the professor is to be believed, then accurately judging the greatness of literary works requires years

of specialized training: accurately judge

training

2. The professor has that training: prof

training

3. The vast majority of the reading public does not have that training: public

NO training
So we need to be careful about what inferences we attempt to draw! Namely, we can say with certainty that the vast majority of the reading public will not be able to accurately judge the greatness of works of literature, since they lack the required element for doing so: specialized training. And that's precisely what (E) tells us! It's simply a combination of the last sentence and the contrapositive of the first.
Diagrammed you'd have the following:

public

NO training

NOT accurately judge
(A), on the other hand, is a Mistaken Reversal trap, where just because the professor has the necessary condition satisfied (she has the specialized training) doesn't guarantee that we can go in reverse against the arrow in the first sentence and say that training tells us she can judge accurately! Put another way: meeting the term at the end of an arrow doesn't allow you to go backwards and arrive conclusively at the first, sufficient term.
Diagrammed it would look like this, where the arrows don't flow in a single direction:

accurately judge

training

professor
Note how we can't get from one end piece to the other without running into the pointy end of an arrow...that means we're stuck! So (A) is trying to get you to commit that classic error, and is therefore incorrect.
I hope that helps!
Jon Denning
PowerScore Test Preparation
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