I'm not sure why the answer to this question is (A) rather than (E). While it is true that the author goes to great lengths to confute the critics of his particular geographical perspective (ie,... "forests, in particular, had been altered to varying degrees well before the arrival of the Europeans"), the author seems more interested in advancing this position in opposition to a previous consensus, rather than merely trying to "(A) refute CERTAIN researchers' views."
(A) just seems too narrow, all the while the author maintains that "the myth persists that in 1492 the Western Hemisphere was an untamed wilderness and that it was European settlers who harnessed and transformed its ecosystems."
To me, that is the "incorrect" myth/record of early-American economical geography that the author seeks to "correct," a la answer choice (E). When in the course of achieving the correction of this record, it is true that the author "refute(s) certain researchers' views." What am I missing here?