The More Restrictive the Government's Immigration Policies Are, the

The more restrictive the government's immigration policies are, the

A) narrower are the wage differentials between countries
B) wider are the wage differentials between countries
C) higher is the migration rate of workers between high-wage and low-wage countries
D) lower are the opportunity costs of work in high-wage countries
E) smaller is the difference between the supply curves of labor in different countries