听力原文:W: What is function of the sale slip? It is so small that it is not always considered important. M: It is small, of course, but it contains the details of the card and they also show the details and amount of the sale. Q: What can we learn from the conversation? (20)
A.
The sales slips are not important.
B.
The sales slips show the amount of the sale.
C.
The sales slips perform. important functions in the bankcard transactions.
D.
The sales slips contain the details of the card.