48. Fresh water is _________ in developing countries. More than one billion people still lack access to safe drinking water, about three billion do not have access to adequate sanitation services, and about two million deaths each year are traced to waterborne diseases. Thus, water there is especially costly or inaccessible to the poorest, while the rich there have it piped into their homes. In addition, because of the infrastructure used to control water, whole seas are being lost, rivers are running dry, or millions of people have been displaced to make room for dams to reserve water.(A) a serious distress(B) a limiting resource(C) a competitive advantage(D) an startling phenomenon