【非谓语选择题】（ ）to sunlight for too much time do harm to one’s sk

【非谓语选择题】（ ）to sunlight for too much time do harm to one's skin.
A.Exposed
B.Being exposed
C.Having exposed
D.After being exposed
答案选B,但我选A,为什么不能选A?为什么要选B?
being，是被动么？

Being exposed to sunlight for too much time will do harm to one's skin.(动名词结构做主语)
==When you are exposed to sunlight for too much time,it will do harm to your skin.（时间状语从句）

主语是being exposed to sunsunshine,谓语是will do harm to,宾语是skin,for too much time是定语.

皮肤被晒伤,所以选择被动,所以是B或者D.但是D不能做主语,因为它前面是个介词,所以只能做状语.
再问： 您好。形容词是不是不能作主语？比如exposed？