Question ID:PT40 S1 Q18 Passage:Bookstore owner:  Consumers should buy books only from an independent bookstore, not from a bookstore that belongs to a bookstore chain. An independent bookstore tends to carry a much wider variety of books than does a chain bookstore, so because chains often threaten the existence of independent bookstores, they tend to reduce the variety of books available to consumers. Stem:Which one of the following principles, if valid, most helps to justify the bookstore owner's argumentation? Correct Answer Choice:BChoice A:Chain bookstores should not force independent bookstores out of business when doing so would reduce the variety of books available to consumers. Choice B:Consumers should buy books from only those bookstores whose existence does not tend to reduce the variety of books available to consumers. Choice C:The best interest of the bookselling business is not served when consumers purchase books from businesses whose existence tends to reduce the variety of books available to consumers. Choice D:Consumers should not make purchases from any bookstore that deliberately forces competing bookstores out of business. Choice E:If consumers have no access to any independent bookstore, they should buy books from the chain bookstore with the greatest diversity of books.