15. What was the three-field system? O A the legal system of medieval Europe
OB an agricultural innovation that increased food yields
OC the economic ownership of a fief and its resources by a lo
OD the political relationship between lords and vassals

B

Explanation:

The three field system allowed nutrients to be replenished in the soil when crops were not being grown, making sure that the soil could stay fertile for longer periods of time.

the answer is bastille

adopted the practice of proskynesis, a persian court custom that involved bowing down and kissing the hand of others, depending on their rank.