Sentence Correction

Transplanting is one of the methods that is commonly used for the seeding of rice in irrigated fields, and is performed either manually or by mechanical transplanting machinery in a variety of spatial configurations.

A. is commonly used for the seeding of rice in irrigated fields, and is performed either manually or by mechanical transplanting machinery in
B. is commonly used for rice seeding in irrigated fields, and is performed either manually or by mechanical transplanting machinery in
C. are commonly used for the seeding of rice in irrigated fields, and is performed either manually or by mechanical transplanting machinery for
D. are commonly used for the seeding of rice in irrigated fields, and is performed either manually or by mechanical transplanting machinery in
E. are commonly used for the seeding of rice in fields that are irrigated, and it is performed either manually or by mechanical transplanting machinery in

OA D

Source: Economist Gmat