单选题 Fewer than half of the jobs in the United States conform even loosely to the standard forty-hour, nine-to-five weekday schedule, according to demographic experts. This is largely due to the rapid increase in the number of service firms and in the proportion of the United States labor force these firms employ, the experts say.
Which of the following, if true, best helps to explain bow the growth of the service sector has had the effect noted above?

A、 In order to supplement their incomes, a small percentage of workers in other sectors of the economy take servicesector jobs as sell.
B、 New service-sector firms have arisen to fill the need for day care for children, a need that was created by the increasing number of families in which both parents are employed.
C、 More part-time than full-time jobs have been created through the application of new technologies to traditional occupations.
D、 Manufacturing enterprises and other nonservice firms often operate twenty-four hours a day, seven days a week.
E、 (E) The largest and fastest-growing segment of the service sector caters to leisure activities pursued outside the standard nine-to-five weekday schedule.

【正确答案】 E

【答案解析】