【正确答案】 A

【答案解析】[听力原文]
Classified advertising is that advertising which is grouped in certain sections of the paper and is thus distinguished from display advertising. Such groupings as "Help Wanted", "Real Estate", "Lost and Found" are made in classified advertisement, the rate charged being less than for display advertising. Classified advertisements are a convenience to the reader and a saving to the advertiser.
The reader who is interested in a particular kind of advertisement finds all advertisements of that type grouped for him. The advertisers may, on this account, use a very small advertisement if it were placed among larger advertisements in the paper. It is evident that the reader approaches the classified advertisement in a different frame of mind from that in which he approaches the other advertisements in the paper. He turns to a page of classified advertisements to search for the particular advertisement that will meet his needs. As his attention is voluntary, the advertiser does not need to rely to much extent on display type to get the reader"s attention. Formerly all classified advertisements were of the same size and did not have display type. With the increase in the number of such advertisements, however, each advertiser within a certain group is competing with others in the same group for the reader"s attention. In many cases, the result has been an increase in the size of the space used and the addition of headlines and pictures. In that way, the classified advertisement has in reality some features of a display advertisement. This is particularly true of real estate advertising.

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