Protection of the environment is based on a principle that is beginning to be used in the

field of jurisprudence. The principle has to do with property rights. The idea is that we all have a property right in the air and water around us. If a business firm pollutes that air or water, their act in so doing constitutes damage to something we own—just as if the firm had dropped a smoke bomb down our chimney. Our legal ease against such a firm is then baaed on the complaint that we deserve compensation for an infringement of our right to use our private property as we please (provided we don' t interfere with the same rights of a neighbor). Assuming we win the case, the offending firm then has to pay us for damaging our property—the air or water we "own".

And so protection of the environment, specifically the control of pollution, now rests on the idea that we, as members of the public, share a right to clean air and water and to the good health that clean air and water quality can give us. But, as always, costs and benefits are involved in any decision to improve the environment.

In an Adam Smithian, self-interested world, entrepreneurs or businessmen are expected to increase their profits as much as possible. The natural way to do this is to produce at the lowest possible cost. But at whose cost？ It is obviously cheaper for entrepreneurs to dump waste into the nearest stream or into the atmosphere than to truck it to some waste disposal facility or to filter it as it comes out of smokestacks. Therefore, what may be sensible for entrepreneurs may not be desirable for the community.

Here is a classic trade-off: When the government intervenes to force entrepreneurs to stop polluting, entrepreneurs have to adopt more expensive means of production or waste disposal. Inevitably, they will charge higher prices, and, given no change in demand, the quantity demanded will drop and workers will be laid off. The trade-off is therefore cleaner air and water or more unemployment. This is how economists view this problem.

According to the passage, the unlawfulness of pollution is relevant to its______.

A．increasing consumption of natural resources

B．ruining effects on the world environment

C．damage to the property owned by other citizens

D．straining of the relations between enterprises and communities