GMAT Sentence Correction (SC) | Re: A mixture of poems and short fiction, Jean Toomer's Cane has

Dear Experts,
I am totally understand OA is always correct, and E is the best of the choices because of parallelism
BUT I am still confused about the use of"being " and the phrase"written by a black American "
1/"being "
I read some posts discussing about the correct use of "being" -- a part of passive voice, and gerund
here, IMO, "being" isneither above situations, SO, I am puzzled

2/ "written by a black American quot;
IMO, written by
...

---