单选题   We can begin our discussion of 'population as a global issue' with what most persons mean when they discuss 'the population problem': too many people on earth and a too rapid increase in the number added each year. The facts are not in dispute. It was quite right to employ the analogy that likened demographic (人口统计学的) growth to 'a long, thin power fuse that bums steadily and haltingly until it finally reaches the charge, and explodes'.
    To understand the current situation, which is characterized by rapid increases in population, it is necessary to understand the history of population trends. Rapid growth is a comparatively recent phenomenon. Looking back at the 8, 000 years of demographic history, we find that populations have been virtually stable or growing very slightly for most of human history. For most of our ancestors, life was hard, often nasty, and very short. There was high fertility in most places, but this was usually balanced by high mortality. For most of human history, it was seldom the case that one in ten persons would live past forty, where infancy and childhood were especially risky periods. Often, societies were in clear danger of extinction because death rates could exceed their birth rates. Thus, the population problem throughout most of history was how to prevent extinction of the human race.
    This pattern is important to know. Not only does it put the current problems of demographic growth into a historical perspective, but it suggests that the cause of rapid increase in population in recent years is not a sudden enthusiasm for more children, but an improvement in the conditions that traditionally have caused high mortality.
    Demographic history can be divided into two major periods: a time of long, slow growth which extended from about 8000 B. C. till approximately 1650 A. D. and a period of rapid, dramatic growth since 1650. In the first period of some 9, 600 years, the population increased from some 8 million to 500 million in 1650. Between 1650 and the present, the population has increased from 500 million to more than 4 billion. And it is estimated that by the year 2020 there will be 8 billion people throughout the world. One way to appreciate this dramatic difference in such abstract numbers is to reduce the time frame to something that is more manageable. Between 8000 B. C. and 1650, an average of only 50, 000 persons was being added annually to the world's population each year. At present, this number is added every six hours. The increase is about 80, 000, 000 persons annually.
单选题     According to the passage, 'population as a global issue' ______.
 
【正确答案】 C
【答案解析】根据题干信息词population as a global issue定位到文章第一段第一句。 根据该句可知：“我们可以用大多数人在讨论‘人口问题’时所指的意思来开始我们对于‘全球性人口问题’的讨论：地球上人口太多，人口年增长速度太快。”即全球性人口问题与人口问题讨论的问题一致，因此全球性人口问题应解决的问题也应是人口问题要解决的，可知C项与上述推断相符，故为答案。 [参考译文] 我们可以用大多数人在讨论“人口问题”时所指的意思来开始我们对于“全球性人口问题”的讨论：地球上人口太多，人口年增长速度太快。这些事实没有任何争议。我们可以将人口增长比喻成“一根又长又细的电力保险丝，时而稳定燃烧，时而又断断续续，直到最终达到电荷限度，爆炸了”。这个比喻相当贴切。 要理解目前以人口剧增为特征的形势，了解人口走势的历史是很有必要的。人口的迅速增长相对来说是最近才出现的现象。回顾8000年采的人口统计历史，我们会发现在人类历史的大部分时期，人口数量几乎一直是稳定的，或者可以说，人口增长幅度是很小的。对于我们的大部分祖先来说，生活很艰辛、恶劣，而且生命非常短暂。大部分地区的生育率都很高，但是，死亡率通常也很高，这使得人口趋于平衡。在人类历史的大多数时期，10个人中很少能有一个活过40岁，其中，婴儿期和儿童期是死亡风险特别大的时期。显然，社会经常面临灭亡的危险，因为死亡率会高于出生率。因此，在人类历史的大多数时期，人口问题都在于如何防止人类种族灭亡。 了解这种模式是很重要的。这不仅使我们能够从历史的角度来看待目前的人口增长问题，而且也暗示着近年来人口剧增的原因不是由于人们突然热衷于生更多的孩子，而是因为长期以来导致高死亡率的条件得到了改善。 人口统计史可以分成两大部分：从公元前约8000年延续到公元1650年左右的长期缓慢增长的时期，以及公元1650年之后的迅速、大幅增长的时期。在这长约9600年的第一阶段，人口从约800万增长到1650年的5亿。从1650年至今，人口从5亿增长到40多亿。据估计，到2020年，全世界人口将达到80亿。要领会这些抽象数字里所隐含的显著差异，一种方法便是将时间段缩小到更便于操控的范围内。在公元前8000年至公元1650年，世界人口平均每年只增加5万人。而现在，每6小时就会增加5万人，即每年大约增加8000万人。
单选题     It can be inferred from the analogy of a power fuse that ______.
 
 
【正确答案】 A
【答案解析】根据题干信息词a power fuse定位到第一段最后一句。 该句将人口增长问题与保险丝作类比，说人口增长就像“一根又长又细的电力保险丝，时而稳定燃烧，时而又断断续续，直到最终达到电荷限度，爆炸了”。由此可推断，人口增长到最后将导致“保险丝的毁灭”，即人类的毁灭，故A项为答案。人口爆炸虽然会导致毁灭性问题，但与地球的毁灭无关，故B项被排除。其他两项本文未提及。
单选题     What leads to a stable growth of population for most of human history? ______
 
 
【正确答案】 D
【答案解析】根据题干信息词stable growth和most of human history定位到第二段第三句和第五句。 题干问“什么导致人口在人类的大部分历史时期增长稳定”，文中提到“回顾8000年来的人口统计历史，我们会发现在人类历史的大部分时期，人口数量几乎一直是稳定的，或者可以说，人口增长幅度是很小的……大部分地区的生育率都很高，但是，死亡率通常也很高，这使得人口趋于平衡”。由此可知，在漫长的历史长河中，大部分时间人口增长稳定，并不是因为其生育能力低等原因，而是因为其死亡率高，故D项符合句意，为正确答案。
单选题     The reason for a rapid growth of population lies in the fact that ______.
 
 
【正确答案】 B
【答案解析】根据题干信息词a rapid growth of population定位到第三段最后一句。 题干问人口快速增长的原因。根据第三段最后一句可知，“……近年来人口剧增的原因不是由于人们突然热衷于生更多的孩子，而是因为长期以来导致高死亡率的条件得到了改善”。由此可知，人口快速增长源于人类生活条件的改善，故正确答案为B。
单选题     How many people are born every six hours at present, according to the author?______
 
 
【正确答案】 C
【答案解析】根据题干信息词every six hours定位到最后一段倒数第二句。 题干问“目前每6个小时有多少人出生”。根据最后一段倒数第二句可知，“而现在，每6小时就会增加到该数目”。根据上下文的逻辑关系可知，本句中的this指代上一句中的数字，即5万，故答案为C。