GMAT Sentence Correction (SC) | Although, shistosomiasis is not often fatal, it is so

Although, shistosomiasis is not often fatal,it is so debilitating that it has become an economic drain on many devloping countries

(A) it is so debilitating that it has become an economic drain
(B) it is of such debilition, it has become an economical
(C) so debilitating is it as to become an economic
(D) such is its debilitation, it becomes an economical
(E) there is so much debilitaiton that it has become