GMAT Sentence Correction (SC) | Re: The Daughters of the American Revolution, a volunteer

The Daughters of the American Revolution, a volunteer service organization,admits as members only women who can prove lineal descent from a patriot of the American Revolution.

The first thing to look for is subject verb agreement between "The Daughter of the American Revolution" and "admits"
Singular subject - Subject Verb

So option B and D are out ..

(A)admits as members only women who can prove lineal descent
"only" correctly modifying "women"
Sentence
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