As long as the resources we consumed each year came primarily from within our own boundaries, this was largely an internal matter. But as our resources come more and more from the outside world, "outsiders" are going to have some stay over the rate at which and terms under which we consume. We will no longer be able to think in terms of "our" resources and "their" resources, but only of common resources.
As Americans consuming such a disproportionate share of the world's resources, we have to question whether or not we can continue our pursuit of super affluence in a world of scarcity. We are now reaching the point where we must carefully examine the presumed link between our level of well-being and the level of material goods consumed. If you have only one crust of bread, then an additional crust of bread doesn't make that much different. In the eyes of most of the world today, Americans have their loaf of bread and are asking for still more. People elsewhere are beginning to ask why. This is the question we're going to have to answer, whether we're trying to persuade countries to step up their exports of oil to us or trying to convince them that we ought to be permitted to maintain our share of the world fish catch.
The prospect of a scarcity of, and competition for, the world's resources requires that we reexamine the way in which we relate to the rest of the world. It means we find ways of cutting back on resource consumption that is dependent on the resources and cooperation of other countries, We cannot expect people in these countries to concern themselves with our worsening energy and food shortages unless we demonstrate some concern for the hunger, illiteracy and disease that are diminishing life for them.
The writer warns Americans that ______.

A. their excessive consumption has caused world resource exhaustion
B. they are confronted with the problem of how to obtain more material goods
C. their unfair share of the world's resources should give way to proper division among countries
D. they have to discard their cars for lack of fossil fuel in the world