50. As a baby emerges from the darkness of the womb with a rudimentary sense of vision, it would be rated about 20/500. or legally blind if it were an adult with such vision.

(A) As a baby emerges from the darkness of the womb with a rudimentary sense of vision, it would be rated about 20/500, or legally blind if it were an adult with such vision.

(B) A baby emerges from the darkness of the womb with a rudimentary sense of vision that would be rated about 20/500, or legally blind as an adult

(C) As a baby emerges from the darkness of the womb, its rudimentary sense of vision would be rated about 20/500; qualifying it to be legally blind if an adult

(D) A baby emerges from the darkness of the womb with a rudimentary sense of vision that would be rated about 20/500; an adult with such vision would be deemed legally blind.

(E) As a baby emerges from the darkness of the womb, its rudimentary sense of vision, which would deemed legally blind for an adult, would be rated about 20/500.

这里A ,C,E选项中的AS的用法正确么，OG解释中并未提到这一点

个人感觉是不太对的

另外 WOULD BE RATED ABOUT 为什么要用虚拟语气呢

RATED ABOUT 20/500 是习语么

Thks

选项中的as为表示时间的连词，“当...时”，

而不是介词结构（介词不能引导从句）；

many thanks !!!!