科学技术的积累和继承要实现，其主要途径是( )。

听力原文：W: Why is the bill of lading so important?M: Because it shows the terms of the contract of carriage, gives evidence of the shipment of goods, and makes sure that the holder of it has the property in the goods.Q: Which is one of the functions of a bill of lading but not mentioned in the conversation?(18)A．The receipt of the goods given by the ship master.B．The evidence of the terms of the contract of carriage.C．The evidence of the shipment of goods.D．The evidence that the holder of it has the property in the goods. 点击查看答案

听力原文：M: I want to apply for a credit card. What are the common credit cards?W: Master Card, Visa, Discover, and American Express. Apply for the ones without annual fees. Some credit cards even pay you back about 1% - 2% of what you spend.Q: Which type of credit card is not mentioned in the conversation?(19)A．Smart Card.B．Master Card.C．Visa Card.D．American Express. 点击查看答案