Context: Kurt is deciding whether to buy a copy of a book or borrow it from the library. He would like to be able to keep the book as long as he wants, but buying the book would cost money. He could borrow the book for free, but he would have to return it in a few weeks.
Suppose Kurt decides to buy a copy of the book. Which result would be a cost?
A. Kurt will get to keep the book as long as he wants.
B. Kurt will spend money to buy the book.
Select the correct answer from the given choices and respond with the letter of the chosen option.

B