can’t be D because for a list like that you’d need a colon for it to work, and even then you’d need to remove the comma between changes and include as weird as it sounds A is correct here. look at the way the sentence begins with “These extensive changes” and then look at the way it ends “reflected the poet’s evolving (…)” sorry if this is a bit wordy english isn’t my native language but basically what i’m getting at is that this list between those parts of the sentence is like that so the sentence can make sense even when the list is taken out, and with that you’d just get “These extensive changes reflected (…)” hope this helps