GMAT Sentence Correction (SC) | The article explained that there is evidence that the

Two consecutive modifiers referring to the same antecedent and without a conjunction is considered awkward in GMAT. In option A " living only an average of 12 years" and "with some even committing suicide" do not have a conjunction between them, and both refer to "dolphins" ( or the entire clause "the dolphins suffer in captivity").
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