问题
单项选择题
The firm's demand curve for labor is:（）
A. identical to the supply curve of the output product.
B. the mirror image of the supply curve of the output product.
C. the downward sloping portion of the marginal revenue product of labor curve.
答案
参考答案：C
解析：
Firms will employ additional labor until the marginal revenue product of labor equals the wage rate. The marginal revenue product falls as the firm increases the use of the resource. The relationship between quantity of labor demanded and wage rate is identical to this negative relationship between quantity employed and marginal revenue product.