The "New Agriculture" of the High Middle Ages

The "new agriculture" of the High Middle Ages

A) resulted from a sharp decline in the total acreage available for farming.
B) was in part brought about by a change from the two-field to the three-field system.
C) led to the demise of the cooperative agricultural villages.
D) was in large part due to the development of a cheap, nonwheeled wooden plow for peasants.
E) was the result of grain imported from the east.