In the United States, the need to protect plant and animal species has become a highly controversial and sharply political issue since the passage of the Endangered Species Act in 1973. The act, designed to protect species' living areas, and policies that preserve land and forests compete with economic interests. In the 1990's, for example, the woodcutters in the Western United States were challenged legally in their attempt to cut trees for timber in the Cascade Mountains. The challenge was mounted to protect the endangered spotted owl (貓頭鷹) , whose remaining population occupies these forests and requires the intact, ancient forest for survival. The problematic situation set the interests of environmentalists against those of corporations and of individuals who stood to lose jobs. After months of debate and legal battles, the fate of the woodcutters—and the owls—was still undecided in mid-1992.
Similar tensions exist between the developed and the developing nations. Many people in industrialized nations, for example, believe that developing nations in tropical regions should do more to protect their rain forests and other natural areas. But the developing countries may be impoverished ( 使窮困 ), with populations growing so rapidly that using the land is a means to temporarily avoid worsening poverty and starvation.
Many of the changes to Earth that concern scientists have the potential to rob the planet of its biological richness. The destruction of Earth's ozone layer( 臭氧層), for example, could contribute to the general process of impoverishment by allowing ultra-violet rays to harm plants and animals. And global warming could wipe out species unable to quickly adapt to changing climates. Clearly, protecting will come only through coordinated international efforts to control human population, stabilize the composition of the atmosphere, and preserve intact Earth's complex web of life.
1. Why does the author say that the protection of endangered species is a highly controversial issue?
A. Because people can't agree as to what species to protect.
B. Because it is difficult to find an effective way to protect such species.
C. Because it affects the interests of certain groups of people.
D. Because it is a major problem involving a series of legal procedures.

2. According to the passage, the preservation of rain forests _____.
A. may hamper developing country in its fight against poverty
B. benefits developed countries rather than developing countries
C. should take priority over the control of human population
D. will help improve the living conditions in developing countries

3. According to the passage, cutting trees to grow more food _____.
A. will widen the gap between the developed and the developing countries
B. is but a short-term relief to the food problem
C. can hardly alleviate the shortage of food
D. proves to be an effective way out for impoverished nations

4. Among "humanity's current problems" (Line6, Para. 3 ), the chief concern of the scientists is _____.
A. the impoverishment of developing countries
B. the explosion of the human population
C. the reduction of biological diversity
D. the effect of global wamfing

5. The author's purpose in writing this passage is _____.
A. to describe the difficulties in solving humanity's current problems
B. to present the different views on humanity's current problems
C. to analyse the contradiction between countries in dealing with humanity's current problems
D. to point out that humanity's current problems can only be solved through the cooperation of nations