Gerrit: While browsing in a record store I noticed that one copy of a recording I wanted had mistakenly been priced at a quarter of the list price. When I finally reached the cashier I was told that the price had been mismarked and I would have to pay the full list price. Since I had wasted an hour standing in line, the retailer was morally obligated to sell me the recording at the lower price. Saskia: I disagree. You knew that a mistake had been made, and you were simply trying to take advantage of that mistake. Which one of the following principles, if established, would most help to justify Saskia's position? ['Customers of retail stores are morally entitled to profit from any mistakes that the retailers make in marking prices.', "Retailers are morally entitled to update marked prices periodically in order to reflect changes in manufacturers' suggested prices.", 'Retailers are morally obligated to sell an item to a customer at a mismarked price only if that customer was genuinely misled about the intended price by the mismarking.', 'The price displayed on an item in a retail store morally constitutes an irrevocable offer to sell the item at that price.']