【正确答案】
C
【答案解析】[听力原文] Let's turn our focus now to advertising. We all know what an advertisement is. It's essentially a message that announces something for sale. Now there is an important precondition that must exist before you have advertising, and that's a large supply of consumer goods, that is, things to sell. You see in a place where the demand for a product is greater than the supply, there is no need to advertise. Now the earliest forms of advertising going back many hundreds of years with a simple sign over shop doors that told you whether the shop was a bakery, a butcher shop or what have you. Then with the advent of printing press, advertising increased substantially. Ads for products like coffee, tea and chocolate appeared in newspapers and other periodicals, as well as on the sides of building. In the American colonies, advertising and communications media like newspapers and pamphlets became a major factor in marketing goods and services. By modem standards, these early advertisements were quite small and subdued, not as splashy, whole page spread of today. Still some of them appeared on the front pages of newspapers probably because the news often consisted of less than fresh reports from distant Europe while the ads were current and local. Advertising really came and became an essential part of doing business during the industrial revolution. Suddenly there was a much greater supply of things to sell. And as we said earlier, that is the driving force behind advertising. People's attention had to be drawn to the new product. Let's take a look at some of the advertisements from that time. What does the speaker say is an important precondition for advertising? 本题问的是“说话者提到的做广告的一个重要的先决条件是什么?”短文提到，在做广告之前必须要有一个先决条件，那就是有大量供消费的商品，即有东西卖。所以，C选项与短文内容相符。