Erin and Deidre, two residents of Ithaca, New York, are planning a trip to Boston. Erin, the sales manager for a large retailer, has to attend a business meeting. Deidre, a college student on vacation, is planning a leisurely trip to visit friends and relatives. Which of the following statements is true?

a. An airline cannot price discriminate because buyers can resell their tickets through the Internet.

b. An airline that price discriminates will charge Deidre a higher price.

c. An airline that price discriminates will charge Erin a higher price.

d. Since there is no difference in the cost of producing air travel, airlines will not charge different prices to Erin and Deidre.