Although the Argentine ant is neither poisonous nor predatory, individual colonies cooperate in a super-colony so large that its collective appetite can become a competitive threat to bird, lizard, and other insect populations.
1) individual colonies cooperate in a super-colony so large that its collective appetite can become a competitive
2)individual colonies cooperate in a super-colony of such size, its collective appetite can become a competing
individual colonies cooperate in a super-colony so large as to cause its collective appetite to become a competitive
such is the size of the cooperative super-colony comprising individual colonies, its collective appetite can become a competing
there is so much size to the individual colonies’ cooperative super-colony that its collective appetite can become a competitive


This is MGMAT CAT Test Question. As per the SC strategy guide regarding usage of pronoun rules the pronoun never refers to nearest noun. However in this sentence the pronoun 'its' refers to super colony . As per the rule it should refer to Ant.

Please clarify this.

is the answer A .

There is NOT a rule that says a pronoun should or should not refer to the closest noun. It has to refer to the correct, unambiguous noun. Often, it's the main subject in the sentence. In the original sentence, its correctly refers to the super-colony.

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