正常新生儿可能引不出的反射是（）

A.巴宾斯基征

B.觅食反射

C.吸吮反射

D.吞咽反射

E.拥抱反射

The quantity of labor that a profit maximizing firm will employ, holding other input factors constant, is the level at which:（）

A. the marginal revenue product of labor is equal to the wage rate.

B. the marginal product of labor is equal to the marginal cost of labor.

C. one more unit of labor would cost less than the value of its additional output.