Passage Summary: Even though there are more people on Earth, we only use a tiny bit of the world's fresh water. Because of this, the author thinks we don't need to worry about running out of water anytime soon.

Conclusion: Predictions that population growth will lead to water shortages in the near future are incorrect.

Reasoning: The current human population only utilizes a small portion of the total available fresh water supply.

Analysis: The author assumes that because the total volume of water is high, it will be accessible and usable for everyone. This ignores the massive logistical hurdles of water distribution and the fact that much of that 'available' water might be in the wrong place or too polluted to drink. To weaken this, we need an answer that explains why a large total supply doesn't guarantee that people won't go thirsty. Look for an answer that highlights issues like geographic distribution or the rate of pollution.