The words “the breadth of my achievement” in this case are literal, for the breadth the author is describing is the thickness of his books and the pages that made up the books. The author is appreciative of the quantity of books he reads rather than the quality of his reading experience or the amount of meaning he’s extracting from his reading. The author is thus confusing quantity with quality. He is mistaking the quantity of his reading for quality. The answer is A.