题目内容：
Passage TwoQuestions 20 to 22 are based on the passage you have just heard. A．It makes buying easier since they needn't carry large amounts of cash.
B．It is useful in times of emergencies like medical bills caused by accidents.
C．It helps build a credit record for bigger purchases in later years.
D．It offers additional protection if something they've bought is lost or damaged.
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