Which statement is NOT an example of price discrimination?

A) Students receive a discount at the ice cream store when they show their college ID cards.
B) Women receive free admission to a nightclub,while men must pay a cover charge.
C) A country club requires members to pay annual dues,but members receive discounted prices to golf (relative to nonmembers) .
D) Street vendors increase the price of umbrellas when it is raining.

Increasing the price of umbrellas when it is raining is not an example of price discrimination. This is simply a case of supply and demand, where the vendor is able to charge a higher price because the demand for umbrellas is higher during rainy weather. Price discrimination involves charging different prices to different groups of customers for the same product or service based on factors such as their willingness to pay, their demographics, or their membership status. Options A, B, and C are all examples of price discrimination.