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题库 / Prep2007E1-CR-26
The population of Megacity, a sprawling metropolis in Remsland, has grown at a fairly steady rate for over a century. A hundred years ago, poor sanitation in the city caused high mortality rates among the city's inhabitants, and what fueled the population increase was immigration from rural villages. This immigration has continued and even increased. Moreover, in recent decades, city sanitation has improved enormously. Yet the city's population growth has not significantly accelerated.
Which of the following, if true, most helps to explain why the city's population growth rate has not changed?
Mortality rates that were associated with poor sanitation in Megacity a hundred years ago were orders of magnitude higher than are mortality rates associated with vehicular traffic, which is currently a major cause of death in the city.
For several decades, Megacity, as distinct from the countryside, has had a steadily declining birth rate.
Cities smaller than Megacity have also experienced sustained population growth.
The great majority of immigrants to Remsland settle in Megacity, at least initially.
Megacity has long offered better employment prospects than most rural areas.
A真的很坑。
说以前因为卫生条件差导致的死亡率高于现在由于交通问题导致的死亡率。
那么...还是说的城市人口的死亡率在剧烈下降...那么伴随着农村移民增加，整个城市的人口应该迅猛增长的啊
B.虽然因为卫生条件而死的死亡率在下降，但是城市人口本身的出生率也在下降，所以可能导致城市人口的变化和卫生条件没改善的时候差不多，这样的话伴随着农村移民的持续增加，城市总人口数变化情况还是和以前的趋势一样
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