In the Accompanying Graphs, the Pre-Migration Labor Force in Country

In the accompanying graphs, the pre-migration labor force in country A is 0d and in country B it is 0u. The migration of labor from low-income country B to high-income country A will

A) increase domestic output in both countries.
B) decrease domestic output in both countries.
C) increase domestic output in country A and decrease domestic output in country B.
D) decrease domestic output in country A and increase domestic output in country B.