单项选择题

Man: I thought the librarian said we could check out as many books as we need with our library cards.
Woman: That's right, but not those reference books.
Question: What does the woman mean

A.Students with a library card can check any book out.
B.Reference books are not allowed to be checked out.
C.Only students with a library card can check out reference books.
D.The number of books a student can check out is unlimite