问题
单项选择题
When workers agree to forego leisure to undertake labor and receive wages, the term that is applied in labor supply economics is the:（）
A. substitution effect.
B. income effect.
C. marginal rate of substitution.
答案
参考答案：A
解析：
In labor supply economics, the term applied to the decision by workers to forego leisure and undertake labor for wages is the substitution effect.