问题
单项选择题
The law of diminishing returns states that at some point:（）
A. as less of a resource are devoted to production, holding the quantity of other inputs constant, the output will decrease, but at an increasing rate.
B. as more of a resource is devoted to production, holding the quantity of other inputs constant, the output will increase, but at a decreasing rate.
C. as more of a resource is devoted to production, holding the quantity of other inputs constant, at some point output will begin to decrease.
答案
参考答案：B
解析：
At low levels of output, increasing marginal returns will exist corresponding to the downward sloping portion of the marginal cost curve. As marginal costs begin to increase diminishing marginal returns will occur.