单选题

A They can buy new books.

B They can change to a computer system.

C They can change the librarians there.

D They can reprint all the cards.

解析：
细节题。针对第一个问题，女士提到“We can either check all the cards and reprint them where necessary, or we can change to a computer system”，即可以检查所有卡片，有必要的话重新印刷，或者改用电脑系统。故选B。