GMAT Sentence Correction (SC) | Re: If medical researchers are correct, then the human microbiome

If medical researchers are correct, then the human microbiome, made up of the microorganisms in our body, may hold the cure to diseases that have long plagued humanity, amounting to a major oversight in Western medicine that has, until recently, all but ignored any such role of the microbiome.

(A) humanity, amounting to a major oversight in Western medicine that has, until recently, all but

(B) humanity, a discovery that amounts to a major oversight in Western medicine, which, until recently,
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