Unlike Colombian coffee, which is generally harvested by hand and immediately threshed, much of that harvested in Brazil is different, as it is mechanically done, and not threshed until after drying.A. Unlike Colombian coffee, which is generally harvested by hand and immediately threshed, much of that harvested in Brazil is different, as it is mechanically done, and not threshed until after drying.
B. Whereas in Colombia coffee is generally harvested by hand and then immediately threshed, in Brazil much of the coffee is mechanically harvested and is dried before it is threshed.
C. In comparison with Colombian coffee, which is generally hand harvested and then threshed immediately, in Brazil much of it is both mechanically harvested and threshed after drying.
D. In contrast with coffee harvesting in Colombia, which is generally by hand and threshed immediately, much of the coffee harvesting in Brazil is done mechanically, and threshing is after drying.
E. Colombian coffee is generally hand harvested, followed by immediate threshing, as opposed to much of Brazilian, which is mechanically harvested and then not threshed immediately afterward.
Source:
TTP Beta Testing
B is much better than other answers that contain some fetal error. In B , i was little susceptible about usage of "it"