单选题   Until the 1980s, the American homeless population is mainly made up of older males. Today, homelessness strikes much younger part of society. In fact, a 25-city survey by the U.S. Conference of Mayors in 1987 found that families with children make up the fastest growing part of the homeless population. Many homeless children gather in inner cities; this transient (变化无常的) and frequently frightened student population creates additional problems—both legal and educational—for already overburdened urban school administrators and teachers.
    Estimates of the number of homeless, Americans range from 350, 000 to three million. Like-wise, estimates of the number of homeless school children vary radically. A U.S. Department of Education report, based on state estimates, states that there are 220,000 homeless school-age children, about a third of whom do not attend school on a regular basis. But the National Coalition for the Homeless estimates that there are at least two times as many homeless children, and that less than half of them attend school regularly.
    One part of the homeless population that is particularly difficult to count consists of the 'throwaway' youths who have been cast of their homes. The Elementary School Center in New York City estimates that there are 1.5 million of them, many of whom are not treated as children because they do not stay in family shelters and tend to live by themselves on the streets.
    Federal law, the Stewart B. McKinney Homeless Assistance Act of 1987, includes a section that addresses the educational needs of homeless children. The educational provisions (规定) of the McKinney Act are based on the belief that all homeless children have the right to a free, appropriate education.
单选题     It is implied in the first paragraph that ______.
 
【正确答案】 C
【答案解析】 根据第一段第四句“this transient and frequently frightened student population creates additional problems—both legal and educational—for already overburdened urban school administrators and teachers.”可知，市区学校的管理者和老师已经负担很重了，但是仍然有聚集的流浪儿童给他们带去额外的问题和麻烦。因此可以推测出教学设施严重短缺，故选C。
单选题     The National Coalition for the Homeless believes that the number of homeless children is ______.
 
【正确答案】 C
【答案解析】 根据第二段最后两句“A U.S．Department of Education report...there are 220,000 homeless school-age children...there are at least two times...”可知，有22万无家可归的学龄儿童，而国家关于无家可归人员的联盟会估计，这样的儿童人数至少还应该多一倍，可知无家可归的孩子的数量是440,000，故选C
单选题     One part of the homeless population is difficult to estimate. The reason might be ______.
 
【正确答案】 D
【答案解析】 根据第三段第一句“One part of the homeless population that is particularly difficult to count consists of the 'throwaway' youths who have been cast of their homes.”可知，无家可归的人口很难估计是因为一些孩子被家庭遗弃，故选D
单选题     The McKinney Act is mentioned in this passage in order to show that ______.
 
【正确答案】 A
【答案解析】 根据最后一段最后一句“The educational provisions of the McKinney Act are based on the belief that all homeless children have the right to a free, appropriate education.'可知，文章提到The McKinney Act是说明无家可归的孩子的教育问题正在被人们意识到，故选A。