GMAT Sentence Correction (SC) | Rallies organized in conjunction with the dissemination

Rallies organized in conjunction with the dissemination of democratic principles which was once prohibited by Communist Chinese leaders, are beginning to take shape at a grass roots level permitted by the new Chinese leadership.

(A) Rallies organized in conjunction with the dissemination of democratic principleswhich was once prohibited by Communist Chinese leaders,are
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(B)Rallies organized in conjunction with the dissemination of democratic principles,
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