阅读理解。 Valuing water Human beings use a little less than half the water available worldwide. Yet shortages and droughts (干旱) are causing starvation and poverty in some areas, and industrial and agricultural by-products are polluting water supplies. Since the world's population is expected to double in the next 51 years, many experts think we are on the edge of a widespread water crisis. But that doesn't have to be the result. Water shortages do not have to trouble the world-if we start valuing water more than we have in the past. Just as we began to value petrol more after the 1970s oil crisis, today we must start looking at water from a fresh economic view. We can no longer afford to consider water a nearly free resource of which we can use as much as we like in any way we want. Instead, for all uses except the demand of the poor, governments should price water to reflect its real value. This means charging a fee for the water itself as well as for the supply costs. Governments should also protect this source by providing water in more economically and environmentally sound ways. For example, often the cheapest way to provide irrigation (灌溉) water in the dry places is through small-scale projects, such as gathering rainfall in depressions(凹地) and pumping it to nearby cropland. No matter what steps governments take to provide water more efficiently, they must change their ways to use water. Rather than control hundreds or even thousands of local, regional agencies that watch water use, countries should set up central authorities to manage water policy. 1. What is the real cause of the potential water crisis? A. Only half of the world's water can be used. B. The world population is increasing faster and faster. C. Half of the world's resources have been seriously polluted. D. Human beings have not placed sufficient value on water resources. 2. We can conclude from the passage that the water problem ______. A. is already serious in certain parts of the world B. has been exaggerated by some experts in the field C. poses a challenge to the technology of building reservoirs D. is underestimated by government organizations at different levels 3. According to the author, the water price should ______. A. be reduced to the minimum B. stimulate domestic demand C. equal its real value D. take into account the occurrences of droughts.