GMAT Sentence Correction (SC) | Re: A supermoon, which is the full or new moon that occurs when the moon i

"Did" and "does" aren't actually pronouns -- in this case, "does" functionssort of like a pronoun, but for verbs. But it definitely isn't a pronoun -- it can just be used to avoid repeating the same verb twice in a sentence:

Shiv2016 studies much more than Carcass studies. --> sounds kind of silly and redundant, right?
Shiv2016 studies much more than Carcass does. --> "does" refers back to "studies", and avoids repetition

So in the original
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