问题
单项选择题
Which of the following condition is least likely to be the obstacle to the efficient allocation of productive resources:（）
A. Price controls
B. Taxes and trade restrictions
C. Perfect competition
答案
参考答案：C
解析：
Some of the obstacles to the efficient allocation of productive resources are: Price controls; Taxes and trade restrictions; Monopoly; External costs; External benefits; Public goods and common resources.