Sentence Correction (SC) | Re: The new University of Michigan study recommends that the state adopt

C,D,E - The word "recommends" triggers subjunctive mood so the verb should be plural
but here "adopts" is used
B - Incorrect subjunctive structure.
A - follows correct structure

Hence A, is the answer.
Check out this blog for the subjunctive structure.
https://www.prepscholar.com/gmat/blog/s ... mood-gmat/

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