[单选题]绝缘斗臂车使用前应在预定位置（ ）试操作一次，确认液压传动、回转、升降、伸缩系统工作正常、操作灵活，制动装置可靠。
A.空斗;
B.载人;
C.模拟;
D.正式

{{U}}The free enterprise system has produced a technology capable of providing the American consumer with the largest and most varied marketplace in the world. Technological advances, however, have come hand-in-hand with impersonal mass marketing of goods and services. {{/U}}Along with progress, too, have come some instances of manipulative advertising practices and a proliferation of products whose reliability, safety and quality are difficult to evaluate.
Today’s consumers buy, enjoy, use and discard more types of goods than could possibly have been imagined even a few years ago. Yet too often consumers have no idea of the materials that have gone into the manufacturer’s finished product or their own motivation in selecting one product over another.
62. {{U}}Easy credit and forceful techniques of modern marketing persuade many consumers to buy what they cannot afford. The consequent overburdening of family budgets is a problem for consum