GMAT Sentence Correction (SC) | Re: All of the letters in the Cyrillic alphabet, one of which is

All of the letters in the Cyrillic alphabet, one of which is borrowed from either the Greek or Latin alphabet, represents specific sounds in spoken Russian.

I chose D over E. Which is wrong after reading OA.


Here, how does verb "represent" refers to All of the letters and not Each of which in the second phrase. Is there any rule to avoid intermittent phrases like this?

Thanks

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