What a fun question!
Our job is to find a flaw in the argument. S.R. Evan's conclusion is that certain critics' judgments should be rejected. Why? Because those critics are not great poets (Evans says "true"), and only true poets can tell if poetry is great. How does Evans know that the critics are not great poets? Because, S.R. Evans explains, she (?) does not find their work to be great.
(BTW, I'm using "great" and "bad" instead of "true", as it's easier to digest the argument that way.)
What a strange argument! It would be valid if we knew for sure that Evans herself is a true poet. We could then apply the principle -- that good poets can tell if a poet is good -- allowing us to trust her judgment of poetry, and then when she tells us the critics have bad poetry, we would believe her, and we would know that those wannabe poet/critics are not qualified to critique poetry (since only true poets can). However, if it turns out that Evans is a crappy poet, then why would we believe her assessment of the critics' poems? And so those critics might actually be great poets, and thus they might be qualified to judge Evans' work (as crappy).
(A) explains this problem with the argument. Evans assumes she herself is a great poet, since otherwise why would she suggest we should accept her assessment of the critics?
(B) is incorrect as there is no distinction made between critics and poets that is relevant to the argument.
(C) is out of scope -- there is no discussion of "the standing of a poet."
(D) is similar to (B) in that it refers to a distinction that is not relevant.
(E) is out of scope - "improve their poetry"?
If a diagram would help:
The argument is: Critics write bad poetry --> critics are not great poet --> critics not qualified to say my poetry sucks
But "Critics write bad poetry", according to the principle stated (judge poetry --> great poet), requires that Evans is a great poet, which is the big IF (assumption) of this argument.