题目解析:
abundantly: 丰富地,大量地。A是偶尔的;B是大量地,丰富地;C是有用地;D是幸运地。所以B的plentifully正确。对应原文:Lichens helped to speed the decomposition of the hard rock surfaces, preparing a soft bed of soil that was abundantly supplied with minerals that had been carried in the molten rock from the bowels of Earth.原句说lichens加快了岩石的分解,怎么样提供了岩石中的mineral,岩石分解了,岩石中的矿物会分散到土壤中,肯定就多了。A的occasionally说反;C和D完全不靠谱。