For Wage Rates to Be the Same in Various Labor

For wage rates to be the same in various labor markets, four conditions must exist: (1) demand for every type of labor must be __________; (2) no special __________ aspects to any job; (3) all labor is ultimately __________ and can __________ be trained for different types of employment; and (4) all labor is mobile at __________.

A) heterogeneous; money; homogeneous; costlessly; minimum cost
B) the same; nonpecuniary; homogeneous; costlessly; zero cost
C) high; training; homogeneous; costlessly; zero cost
D) high; nonpecuniary; heterogeneous; costlessly; minimum cost