The demand for plumbers is the same in country A and country B, but the plumbers in country A earn less than the plumbers in country B. What can explain this difference?

Select one:

a.The supply of plumbers is greater in country B than country A.

b.The economy of country A is more productive than the economy of country B.

c.The supply of plumbers is greater in country A than country B.

d.The economy of country B is more productive than the economy of country A.