Most Mexican workers can increase their wages if they migrate to the United States, a demand-pull factor for migration

How does the United States differ from the European Union in how it balances the competing claims of equality and efficiency?

Refer to the diagram, where variable inputs of labor are being added to a constant amount of property resources. The total output of this firm will cease to expand:

A. if a labor force in excess of Q 1 is employed.
B. if a labor force in excess of Q 2 is employed.
C. if a labor force in excess of Q 3 is employed.
D. only if the marginal product curve becomes negative at all levels of output.