[单项选择]在多囊肝的描述中，错误的是
A. 是一先天性疾病
B. 早期可无明显症状
C. 肝脏体积增大，密布大小不等的囊腔
D. 囊壁不均匀增厚，并可见乳头状突起
E. 常合并肾脏等其他脏器的多囊性病变

{{B}}Earth: Melting in the Heat {{/B}}
Glaciers are melting; the ice caps are disappearing into the oceans; sea levels may rise by many meters as a consequence. Indigenous (本土的) Arctic peoples will find their food stocks gone, while fresh water supplies in Asia and south America will disappear as the glaciers which provide them melt away; penguins, polar bears and seals will find their habitats gone, their traditional lives unlivable.
But how realistic is this picture Is the world’s ice really disappearing, or is it unscientific hot air
A European satellite named Cryosat was designed to provide definitive answers to some of these questions. A launcher fault destroyed the mission in October 2005, but the European Space Agency has approved a replacement. In the meantime, here is our global snapshot.
{{B}}The Antarctic{{/B}}
Huge, pristine (质朴的), dramatic, unforgiv