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A) is what they can not affordB) is not a practical solution

C) won’t cost a lot of moneyD) is effective but expensive

25. It is implied in the last paragraph that          .

A) people should be taught how to escape the tsunami

B) a sound detection system could have saved the disaster

C) radio stations neglected their responsibilities

D) the heavy loss in the Southª²East tsunami could have been less

Passage Two

Questions 26 to 30 are based on the following passage.

Ever since Darwin’s theory of evolution, biologists have assumed that environments teeming with complex forms of life served as the nurseries of evolution. But two recent papers in Science magazine have turned that notion on its head. Last month some biologists reported that in the ocean it is the relatively barren areas that serve as “evolutionary crucibles(ÈÛ¯),” not regions with great diversity of species. Other researchers announced this summer that the Arctic, not the rain forest, spawned many plants and animals that later migrated to North America. Says John Sepkoski of the University of Chicago, “Harsh environments may be producing the major changes in the history of life.”

These “changes” do not result merely in a longer tail or a bigger claw for an existing species but, rather, in dramatic leaps up the evolutionary ladder—a rare innovation that comes along once in a million years. In the Arctic, reports Leo Hickey of Yale University, the innovations ran to forms never before seen on earth. By dating fossils from many geologic layers, he concluded that large grazing animals first appeared in the Arctic and migrated to temperate places a couple of million years or so later. Among plants, species of redwood and birch originated in polar regions some 18 millions years before they showed up in the south. Examining fossils as old as 570 million years, Chicago’s Sepkoski found that shell-