Which sentence best illustrates the authors central argument in this passage? passage: the harsh ethics of the lifeboat become even harsher when we consider the reproductive differences between the rich nations and the poor nations. the people inside the lifeboats are doubling in numbers every 87 years; those swimming around outside are doubling, on the average, every 35 years, more than twice as fast as the rich. and since the world's resources are dwindling, the difference in prosperity between the rich and the poor can only increase. as of 1973, the u. s. had a population of 210 million people, who were increasing by 0.8 percent per year. outside our lifeboat, let us imagine another 210 million people (say the combined populations of colombia, ecuador, venezuela, morocco, pakistan, thailand and the philippines) who are increasing at a rate of 3.3 percent per year. put differently, the doubling time for this aggregate population is 21 years, compared to 87 years for the u. s. the harsh ethics of the lifeboat become harsher when we consider the reproductive differences between rich and poor. apex