GMAT Sentence Correction (SC) | When drafting the Declaration of Sentiments that was adopted

E is the correct answer
E is preferred because it has a direct or active voice

A although seems correct but has indirect or passive voice that GMAT avoids.
Also A wrongly modifies "Seneca Falls Women’s Rights Conventions in 1848, included in it by the author"
Nothing was included in convention, something was included in the declaration of sentiment.

When drafting the Declaration of Sentiments that was adopted at the[s] Seneca Falls Women’s Rights Conventions in 1848,
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