It would be the last one!!!!!
Production of more food--the system allowed for more food to be produced which fed the workers in an industrial economy.
The 'four-field system' rotates crops between the 4 fields no longer needing to keep one empty because one of the crops would replenish the field with nutrients while the others take nutrients away from the fields. <span />
Generally speaking, advanced farming techniques allowed for a surplus of food, which led to the emergence of a "artisan" class--since for the first time people were "freed" to engage in other actives besides gathering food.
I believe it’s D or C it’s one of those