Sentence Correction

Although some officials noted that using machines for farming in China costs more than traditional hand cultivation, "the mechanization of farming in the village of Long Bow doubled the corn yield while the previous year's costs were cut in half."
(A) mechanization of farming in the village of Long Bow doubled the corn yield while the previous year's costs were cut in half
(B) mechanization of farming in the village of Long Bow doubled the corn yield while cutting costs to half those of the previous year
(C) mechanization of farming in the village of Long Bow doubled the corn yield as cost were cut to half of the previous year's
(D) farming mechanization in the village of Long Bow doubled the corn yield as it cut in half the previous year's costs
(E) farming mechanization in the village of Long Bow doubled the corn yield while costs were cut to half that of the previous year

hritik wrote:Although some officials noted that using machines for farming in China costs more than traditional hand cultivation, "the mechanization of farming in the village of Long Bow doubled the corn yield while the previous year's costs were cut in half."
(A) mechanization of farming in the village of Long Bow doubled the corn yield while the previous year's costs were cut in half
(B) mechanization of farming in the village of Long Bow doubled the corn yield while cutting costs to half those of the previous year
(C) mechanization of farming in the village of Long Bow doubled the corn yield as cost were cut to half of the previous year's
(D) farming mechanization in the village of Long Bow doubled the corn yield as it cut in half the previous year's costs
(E) farming mechanization in the village of Long Bow doubled the corn yield while costs were cut to half that of the previous year

Mixed with E and B
How to choose between them?

What is the OA?

Please take a few seconds to underline the SC question for the benefit of other forum members.

costs is plural . In e , that is singular . Therefore B