Sentence Correction (SC) | Re: The earliest formal number systems, complete with place values such as

OFFICIAL SOLUTION

Anytime you see a clear subject-verb agreement decision point in the answer choices – here the choice between “date” and “dates” – start by analyzing that. Using slash-and-burn to get rid of modifiers, you see the core sentence for (C), (D), and (E) is really: The systems…DATE BACK or DATES BACK. Since “systems” is plural you must have the plural verb “date” to make it correct – (C) and (D) can be confidently eliminated.
(A) and (B) have a completely different
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