19. GWD17-Q19:

Regardless of their form or function, all aerodynamically enhanced, curved objects made for throwing have been called boomerangs by non-Australians even since 1788, when Europeans saw Dharug-speaking men tossing “bumariny” in the area later known as Sydney.

1. Regardless of their form or function, all aerodynamically enhanced, curved objects made for throwing have been called boomerangs by non-Australians ever since 1788,
2. Regardless of their form or function, any aerodynamically enhanced, curved object made for throwing has been called a boomerang by non-Australians ever since 1788,
3. Ever since 1788, non-Australians have called all aerodynamically enhanced, curved objects made for throwing boomerangs, regardless of their form or function, from
4. Ever since 1788, any aerodynamically enhanced, curved object made for throwing has been called a boomerang by non-Australians, regardless of its form or function, from
5. Non-Australians have called all aerodynamically enhanced, curved objects made for throwing boomerangs ever since 1788, regardless of their form or function, from

答案是E，我选的是A，后来觉得E中虽然主动替换了原句的被动是正确的，但是仍然无法理解最后那个介词,from，请教各位NN解答一下when的前面为什么要加from？

不是C???

E不如C好，

it becomes unclear what "regardless of their form or function," is

modifying. 

请NN指教

楼主,我这边的gwd31套给出的答案是a,本人也觉得a没有什么太大的问题...