问题
单项选择题
Which of the following is least likely to be considered a necessary condition for a monopolist to realize profits from price discrimination（）
A. A product for which the demand curve is downward sloping.
B. At least two groups of customers, each with a different price elasticity of demand.
C. Two different costs of production.
答案
参考答案：C
解析：
Price discrimination works when the seller (discriminator) faces a downward-sloping demand curve and has at least two customer groups each having different price elasticities for the product. It is also necessary that trading does not occur between customer groups so that the customers paying a lower price cannot resell the product to the customers paying a higher price.