GWD SC 题不懂，求助！

TheGreek

Studying the fruit fly, a household nuisance but a time-honored experimental
subject, has enabled the secrets of how embryos develop to begin to be
unraveled by scientists,

A  Studying the fruit fly, a household nuisance but a time-honored experi-mental subject, has enabled the secrets of how embryos develop to begin to be unraveled by scientists.  

B.By the study of the fruit fly, a household nuisance and also a time-honored experimental subject, it was possible for the secrets of how embryos develo0p to begin to be unraveled by scientists.  

C .By studying a household nuisance but a time-honored experimental sub-ject, the fruit fly enabled scientists to begin to unravel the secrets of how embryos develop.  

D .By studying the fruit fly, a household nuisance and also a time-honored experimental subject, the secrets of how embryos develop are begin-ning to be unraveled by scientists.  

E. The study of the fruit fly, a household nuisance but a time-honored exper-imental subject, has enabled scientists to begin to unravel the secrets of how embryos develop.  
我选的A,答案是E，认为E中enable的发起者可以是subject或The study of the fruit fly。所以觉得E不对，求NN解释，为何选E!谢谢！

TheGreek

E项不存在歧义吗？我觉得E项的发起者不明啊，求解答！

cherryserena

还有 A中动名词 Studying 是否可以用同位语！！！！这个值得考证！

supercury

这个解释比较牵强，因为A选项的a household nuisance but a time-honored experimental subject是做同位语的。C和D倒是存在studying的逻辑主语问题。
比较A和E，主动比被动好。