听力原文：W: With the convenience of bankcards, more and more people prefer bankcards to personal checks.M: I agree. People like bankcards because they offer greater safety and convenience than personal checks.Q: What can be inferred from the conversation?(20)
题目
听力原文：W: With the convenience of bankcards, more and more people prefer bankcards to personal checks.
M: I agree. People like bankcards because they offer greater safety and convenience than personal checks.
Q: What can be inferred from the conversation?
(20)
A．A merchant doesn't know the balance before completing a sale.
B．No security system has yet been devised for personal checks.
C．A personal check is secure at the check stand.
D．The clerk can examine all the bankcards.