求教这道kaplan语法！谢谢

6. Researchers are studying plastics that dissolve at different rates, and they are finding that the so-called 'quick disintegration' plastics are taking more time to deteriorate than they originally seemed.

a) they originally seemed

b) they seemed originally

c) it seemed that they would originally

d) it originally seemed                                                  

e) it originally seemed they would

这个题的答案是E，谁可以把E省略的成分补全了，我对这个答案还是有些糊涂，thanks~~~~~~~~~~~~

求教ing~~~~~~~~~~~~~~~~~~```