According to the United Nations, the total fertility

According to the United Nations, the total fertility rate - the number of children a woman may be expected to bear during her lifetime - has fallen in every region of the world since 1950. From an average of nearly six children per woman in the 1950s, total fertility rate fell to three children in Latin America, 3.4 in India, and 3.5 in other parts of Asia by the early to mid-1990s. The only major exception to this sustained downtrend is in North America, where the recent increase in total fertility rate appears to be a transitory phenomenon associated with immigration and a large number of baby-boom women deciding to have children relatively late in their lives.

As significant as declining total fertility rates worldwide is the fact that, from 1990 to 1995, the rates in Europe, China, and North America were below the 2.1 average children per woman needed to sustain population worldwide over the long run.  The United Nations' medium population projection of 2.1 children after 2040 is widely used as a demographic forecast, but it unrealistically assumes that this rate will be the same in both developed and developing countries. Many researchers, such as Wolfgang Lutz of the International Institute for Applied Systems Analysis, do not support the UN assertion that fertility would increase to replacement level in developed countries. Lutz and others cite evidence pointing toward low fertility, noting contraception, declining marriage rates, high divorce rates, increasing independence and career orientation of women, materialism, and consumerism.

"These factors, together with increasing demands and personal expectations for attention, time, and also money to be given to children, are likely to result in fewer couples having more than one or two children and an increasing number of childless women," Lutz and his colleagues write in The Future Population of the World.  The United Nations has a second scenario - the low/medium scenario - that presumes fertility averaging 1.9 children per woman for all regions by 2025. This scenario may be as unrealistic as the medium population scenario. The low/medium scenario may underestimate future total fertility rates in developing countries, just as the UN medium scenario may overestimate future total fertility rate in developed countries.

The low/medium scenario projects a peak world population of 7.9 billion people in 2050, declining to 6.4 billion by 2150. The medium scenario projects a peak world population of just less than 11 billion by approximately 2200. Most other projections, however, predict peak global population in less than a century, followed by negative population growth.
These 1998 UN population figures were revised in 2000, and the new estimates, though tentative, indicate population trends even lower than the 1998 predictions. The low/medium scenario is comparable to what the United Nations now calls the low variant for worldwide populations. Given the low variant, the United Nations predicts that world population in 2050 will be 7.8 billion--slightly less than the 7.9 billion projected under the low/medium scenario. It is predicted that the United Nations will continue to revise population trends downward and that negative population growth will occur even sooner than 2150. However, because the 2000 population data remain tentative and do not extend to 2150, it is preferable to continue to rely on the 1998 data.

1. Which of the following statements can be inferred from the passage?
 
(A) immigrates to the United States give birth to fewer children than they would have, had they remained in their native countries
(B) immigrates to the United States give birth to more children than they would have, had they remained in their native countries
(C) more immigrates to the United States give birth to fewer children than they would have, had they remained in their native countries
(D) less immigrates to the United States give birth to more children than they would have, had they remained in their native countries
(E) immigrates to the United States give birth to fewer children, on average, than native born American woman

The best answer is E. Since elevated fertility rate can be partly accounted for by immigration, it can be inferred that the immigrants give birth to more children than do native Americans, on average.

2.  It can be inferred from the passage that
(A)  the birth rate in South-East Asia has risen since the 1950s
(B)  the birth rate in Africa has declined since the 1950s
(C)  the birth rate in North America has declined since the 1950s  
(D)  the birth rate in North America is higher than the death rate
(E)  the birth rate in North America is lower than the death rate

The best answer is B.   According to the passage the fertility rate has declined in every region of the world except North America, therefore it can be inferred that the fertility rate dropped in Africa.

3.  According to predictions made by Wolfgang Lutz, which of the following is likely to occur?
(A)  More women in future will remain childless than do so today.
(B)  More woman will put off having children until their thirties than do so today
(C)  More woman will give birth one or two babies than do today.
(D)  Less women will choose not to have children.
(E)  The number of children a couple has will be determined more and more often by the female partner.

The best answer is A.  According to the passage, Wolfgang Lutz predicts that various factors will lead to an increasing number of childless women.

4.  According to the United Nation’s projected demographics, the low/medium forecast predicts
(A) a peak in approximately 2050 while the medium forecast predicts a peak in approximately 2200
(B) a peak in approximately 2050 while the medium forecast predicts a peak in approximately 2150
(C) a peak in approximately 2150 while the medium forecast predicts a peak in approximately 2050
(D) a peak in approximately 2150 while the medium forecast predicts a peak in approximately 2200
(E) a peak in approximately 2200 while the medium forecast predicts a peak in approximately 2150

The best answer is  A.  The low/medium forecast predicts that the population will reach its highest point – 7.9 billion – in approximately 2050.  The medium forecast predicts that the population will reach its highest point – 11 billion – by approximately 2200.