Although schistosomiasis is not often fatal, it is so debilitating that it has become an economic drain on many developing countries.
(A)it is so debilitating that it has become an economic
(B)it is of such debilitation, it has become an economical
(C)so debilitating is it as to become an economic
(D)such is its debilitation, it becomes an economica
(E)there is so much debilitation that it has become an economical
题目分析：A读完之后逻辑比较通顺，留着。B选项改用economical了，那意思就变成“节约的”，意思不对，干掉。同理，D和E也可以干掉。A和D进行比较，显然A通顺很多。选A
