GMAT Sentence Correction (SC) | An international convention regulating trade in endangered

An international convention regulating trade in endangered species, especially bears and tigers,could be significantly weakened were it not for restrictions on captive breeding of endangered species, warn conservation and animal welfare groups.

(A) could be significantly weakenedwere it not for restrictions on captive breeding of endangered species, warn conservation and animal welfare groups.

(B) could be significantly weakened if restrictions on captive breeding of endangered species aren't
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