Although this question has been discussed here https://www.beatthegmat.com/so-x-as-to-b ... html#34404
no further discussions were added. Hence, I am re-opening the thread

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.

A) individual colonies cooperate in a super-colony so large that its collective appetite can become a competitive

B) individual colonies cooperate in a super-colony of such size, its collective appetite can become a competing

C) individual colonies cooperate in a super-colony so large as to cause its collective appetite to become a competitive

D) such is the size of the cooperative super-colony comprising individual colonies, its collective appetite can become a competing

E) there is so much size to the individual colonies’ cooperative super-colony that its collective appetite can become a competitive

Why OA is [spoiler][A][/spoiler]. Please explain.