Two college students, Mary and Maggie, are spending spring break in Florida. Mary buys a cup of coffee each morning at the local Starbucks rather than from one of the local coffee shops. Maggie claims that Mary is irrational because she never purchases Starbucks coffee at home, and Starbucks coffee costs more than the coffee sold by local shops. An economist would most likely explain Mary’s behavior by suggesting that a. Mary’s behavior is clearly irrational, but Maggie’s behavior is rational. b. the advertising by Starbucks in Florida is more persuasive than the advertising by Starbucks in Mary and Maggie’s home town. c. the Starbucks brand name suggests consistent quality. d. Mary’s behavior is rational, but Maggie's behavior is clearly irrational.