题目

Overflowing rivers can cause enormous damage. 【1】 And it continues to rise. So far it has not been evident how climate change influences the magnitude (规模) of river floods.Austrian flood expert Prof. Günter Blöschl from TU Wien (Vienna) has led a large international study involving a total of 35 research groups. The study provides clear evidence that it is climate change that causes the change of magnitude of flood events observed in recent decades. 【2】 In northwestern Europe, floods are becoming increasingly severe; in southern and eastern Europe, flood magnitudes mostly tend to盒中有10个大小、形状完全相同的小球,其中8个白球、2个红球,则从中任取2球,至少有1个白球的概率是(    )A.            B.             C.              D.