OG diag 26 没有讨论~

Guillemots are birds for arctic regions. They feed on fish that gather beneath thin sheets of floating ice, and they nest on nearby lands. Guillemots need 80 consecutive snow free days in a year to raise their chicks, so until avrage temperature in arctic began to rise recently, the guillemots' range was limited to the southernmost arctic coast. Therefore, if the warming continues, the guillemots' range will probably be enlarged by being extended northward along the coast...

Which of the following, if true, most seriously weakens the the argument?

A. Even if the warming trend continues, there will still be years in which guillemots chicks are killed by an unusually early snow.
B. If Arctic warming continues, guillemots' current predators are likely to succeed in extending their own range farther north
C. Guillemots nest in coastal areas, where tempratures are generally higher than inland areas.
D. If the Arctic warming continues much of the thin ice in southern arctic will disappear.
E. The fish that guillemots eat are currently preyed on by wider variety of predators in southernmost arctic regions than they are farther north.

答案是D，可是我想不通呀，南边的冰消失了，跟鸟的范围会不会到北边没什么关系吧~~

请求帮助~~~~