Less accessible than in hieratic form, but precisely for this reason

A. Less accessible than in hieratic form, but precisely for this reason the cursive form of ancient Egyptian ideographic writing was more suitable for sacerdotal uses - Incorrect
"Less accessible than in hieratic form" should be followed by a noun which is modified by this phrase. But here, it is ambiguous as "the cursive form" is pretty far away, which is intended to be modified by the meaning of the sentence.

B. The reason the cursive form of ancient Egyptian ideographic writing was more suitable for sacerdotal uses than the hieratic form was is precisely because it was less accessible - Incorrect
"was is"???? Two forms of verb together? Really strange construction, and absolutely incorrect.

C. Ancient Egyptian ideographic writing in its cursive rather than hieratic form was more suitable for sacerdotal uses precisely because less accessible - Incorrect
What is less accessible? Even though in our minds we think it is talking about "ancient Egyptian ideographic writing in its cursive form" only, but there's nothing pointing to it, there should be a pronoun in the last phrase.

D. Being less accessible as compared to the hieratic form, the cursive form of ancient Egyptian ideographic writing was more suitable for sacerdotal uses precisely because of this. - Incorrect
Be on a lookout as soon as you see "being" in the sentence, more often than not, this answer choice will be wrong. (But do keep in mind, in a few cases, being is correctly used)
can follow this thread for better understanding: https://gmatclub.com/forum/usage-of-bei ... 11592.html
Here, as mentioned in other explanations, the culprit is "this" at the end. What does "this" point to? It's not abundantly clear, we will need to scratch our heads a bit for it, and that is an indicator that this answer choice is going to be incorrect.

E. Precisely because it was less accessible than the hieratic form, the cursive form of ancient Egyptian ideographic writing was more suitable for sacerdotal uses - Correct
Usage of it in the first part is properly justified, as it clearly points only to the "cursive form of ancient Egyptian ideographic writing" and there's no other noun it could point to. Hence, correct.

Thus, correct answer is E