136. 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 economical E.there is so much debilitation that it has become an economical
请问C为什么错?OG上的解释:and C uses an awkward and wordy construction in place of a that... clause.请问谁能把它解释清楚?谢谢!