Which of the Following Was an Important Consequence of Increased

Which of the following was an important consequence of increased output of food in the countryside under Song rule?

A) China's cities shrank as people moved to the countryside to take part in the agricultural upswing.
B) A wealthy and prosperous peasantry began to rally for its rights.
C) China traded less with foreigners, as they were able to sustain the population on their own.
D) China's cities grew, and artisans were able to focus more on their crafts.