why not e?

I am wondering the same thing… Perhaps it could be that answer C implies that the small idiosyncrasies are more likely to identify if the poem does not belong to an author, given that the tiny peculiarities could be widely spread? I don't know to be honest and need help…

Great question. Let’s begin by breaking the argument down: Premise 1: If peculiarities appear in the work of multiple poets, it is likely common language at the time Premise 2: If peculiarities appear in the work of just one poet, it is likely to be personal idiosyncrasies Conclusion: The peculiarities can be used to determine who wrote poems of unknown authorship As with any question that contains an argument, you want to be critical upon reading it. Ask whether this conclusion seems to follow from the evidence, and if not, ask yourself what the weaknesses of the argument are. Then, in the context of a weaken question, attempt to expose those weaknesses. Do this before reading the answer choices. The problem that I see here initially is that the conclusion seems to be ignoring premise 1. If we have language in a poem of unknown authorship that is similar to the language of a poem of which we know the author, it could just as easily be evidence that the language is simply common language. Answer choice C exposes that weakness. Answer choice E is out of scope because it is about conscious vs unconscious use of language, rather than common vs idiosyncratic. Whether or not the language was used consciously has no impact on whether it constitutes common language. Therefore, that answer choice would not affect the argument one way or the other. Hope this helps!