#12 - Though Earth’s human population is increasing

[Adam Tyson]

Answer C doesn't matter, Becca1924, because the author has told us that there is plenty of water available. Even if nobody conserves water, the author thinks there will still be plenty to go around, at least for the near future before the population gets too big. And this answer doesn't even say that nobody will conserve, but just that not everyone will. So what, who cares? There's water everywhere!

Of course, the real problem is that while there may be a lot of water, not everyone can get access to it. This is like saying "the banks are full of money, so nobody should be poor" or "there are more cars in this country than there are people, so nobody should be unable to get a car." If you cannot get your hands on a resource, or cannot afford it, then it doesn't matter that there is plenty; you will still have to go without.

[queenbee]

Hi
If the stimulus states that the earths population is increasing, is it not thinking about the earth as a whole? And if as a whole we are using a very small percentage of the water, what difference does it make if one region is consuming more than another? we have enough either way because we are using very little.

There were 2 major ways i though there could be a flaw: 1. We did not predict population growth accurately, or 2. there is another source of depleting the water supply (global warming, and unexpected industrial use, etc). It seemed like B captured that thought. Though the population may not be increasing fast enough to deplete the vast supplies we had, other things would.

Would you please help me with this one?
Thank you

[Luke Haqq]

Hi queenbee!

Happy to address this question. First, it's great that you thought of two potential flaws that the stimulus might contain. Pre-phrasing answers like that is a useful practice to be in the habit of doing and can make one more prepared for the answers, even if the pre-phrase doesn't end up being in the answer choices.

The final sentence provides the conclusion or argument of the stimulus: "Thus, claims that water shortages will plague humankind in the near future unless population growth trends change are simply mistaken." Why does the author conclude that these claims are mistaken? This reasoning is in the first sentence, namely, the author thinks that there will not be shortages in the near future (unless population growth trends change) because we only use a fraction of the Earth's water supply. Given the question stem, we are then asked to weaken the conclusion that this claim is mistaken, that is, weaken the connection that using only a fraction of the Earth's supply is reason for concluding that water shortages will plague humankind in the near future.

You ask,

And if as a whole we are using a very small percentage of the water, what difference does it make if one region is consuming more than another? we have enough either way because we are using very little.

Answer choice (B) gets at and weakens the above connection: "The amount of fresh water available to meet the needs of Earth’s population varies significantly from region to region." If this were true, then it opens up the possibility that some regions (such as deserts) might still encounter water shortages in the near future, even if humankind overall only uses a fraction of it. Even if there is an overabundance of it, there could be matters like a lack of infrastructure and transportation that could impede getting fresh water to regions that might have less access to it or not enough to meet the needs of the Earth's population in those areas. In short, it shows that there could still be water shortages in the near future.