In the Past,China Limited the Movement of Workers from Rural

In the past,China limited the movement of workers from rural to urban areas.When it got rid of these limits,one would expect

A) urban wages to rise in order to attract rural workers.
B) rural wages to fall as workers leaving depress the rural area.
C) national output to rise as workers are better matched with employers.
D) national output to fall due to higher total mobility costs.