在寒冷的北方，池塘冰面上的空气温度为-10℃，在下述几种情况中，温度恰为0℃的是
题型：选择题
问题：
在寒冷的北方，池塘冰面上的空气温度为-10℃，在下述几种情况中，温度恰为0℃的是（ ）
A．冰层的上表面
B．冰层的下表面
C．冰层下面所有的水
D．除了冰层上表面以外的冰
题型：选择题
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