下列各组物质，均属于纯净物的是（ ）
A．粗盐、牛奶
B．铝合金、铁锈
C．冰水混合物、氧气
D．生理盐水、纯净水
答案：C
Do you think shopping online will _____ take the place of shopping in stores? [ ]
A. especially
B. frequently
C. merely
D. finally
在党的十一届三中全会上，全面系统地阐述了社会主义初级阶段理论。( )
