Sentence Correction (SC) | Re: Nineteenth-century doctors thought that alcohol, when ingested, passed

Nineteenth-century doctors thought that alcohol, when ingested, passed through the stomach into the bloodstream and was broken down only by the liver; recent studies, however,have led them to conclude that the stomach breaks down up to 20 percent of ingested alcohol before it reaches theliver.

[A] have ledthem to conclude ---it means the doctors who were mentioned before - the nineteeth-century doctors
[B] have led totheir conclusion ---same as A
[C] have led doctors to conclude
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