问题
单项选择题
The presence of which of the following is mostly likely to result in the overproduction of the efficient quantity of goods of services in a market economy（）
A. Perfect competition.
B. Taxes on sales.
C. Monopoly.
答案
参考答案：C
解析：
A decrease in the price of a substitute resource would induce producers to use the substitute resource, reducing demand for the resource in question. An increase in the price of a complementary resource would decrease demand for both resources.
