TOEFL Listening: TPO-TOEFL听力TPO - 728_6W41FKKX454NR$

Why does the man say this: A. To acknowledge that there is a problem with the reserve system B. To indicate how the library avoids the problem the student mentioned C. To explain why the library has ordered more copies of the book D. To reinforce the reason why so many books are not on the shelves