Sentence Correction

In 1791 Robert Carter III, one of the wealthiest plantation owners in Virginia, stunned his family, friends, and neighbors by filing a deed of emancipation, setting free the more than 500 slaves who were legally considered his property.
(A) setting free the more than 500 slaves who were legally considered
(B) setting free more than the 500 slaves legally considered as
(C) and set free more than 500 slaves, who were legally considered as
(D) and set free more than 500 slaves who were legally considered
(E) and he set free the more than 500 slaves who were legally considered as

OA is A

Please could you share your reasoning? Thanks.

kartyc wrote:In 1791 Robert Carter III, one of the wealthiest plantation owners in Virginia, stunned his family, friends, and neighbors by filing a deed of emancipation, setting free the more than 500 slaves who were legally considered his property.
(A) setting free the more than 500 slaves who were legally considered
(B) setting free more than the 500 slaves legally considered as
(C) and set free more than 500 slaves, who were legally considered as
(D) and set free more than 500 slaves who were legally considered
(E) and he set free the more than 500 slaves who were legally considered as

OA is A

Please could you share your reasoning? Thanks.

https://www.beatthegmat.com/robert-carter-t24451.html

boss only one point: considered as is incorrect idiom when bla bla bla...

so BCE are out
out of A D A is correct....because of filling the dead of emancipation and setting free are not two parallel activity....ope it helps...