我国的基本民族政策是（）。
A、实行民族区域自治
B、实现各民族共同繁荣
C、民族不分大小一律平等
参考答案：C
Over the past decades, sea ice _________ in the Arctic as a result of global warming. [ ]
A. had decreased
B. decreased
C. has been decreasing
D. is decreasing
12个啤酒空瓶可以免费换1瓶啤酒，现有101个啤酒空瓶，最多可以免费喝到的啤酒为（）。
A．10瓶
B． 11瓶
C． 8瓶
D． 9瓶
