GMATPill wrote:
Many scientists say that attempts to remove a species of the black bee in India did not work because the pesticides that were utilized were effective only in eradicating the natural enemies of the black bee, which made it easier for them to grow and proliferate.
(A) which made it easier forthem
WRONG. -USE OF WHICH AND THEM is ambiguous
(B) which makes it easier forit
WRONG -USE OF WHICH IS AMBIGUOUS
-IT =SINGULAR while SPECIES = PLURAL...pronoun number error.
(C) thus making it easier
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