以硫酸铜溶液作电解液，对含有杂质Fe、Zn、Ag的粗铜进行电解精炼．下列叙述正确的是（ ）
①粗铜与直流电源负极相连
②阴极发生的反应为Cu2++2e﹣=Cu
③电路中每通过3.01×1023个电子，得到的精铜质量为16g
④杂质Ag以Ag2SO4的形式沉入电解槽形成“阳极泥”
A：②③
B：②④
C：③④
D：①③
①Do you like the red hat? ____ A. He is under the tree.
②Where's the old man? ____ B. No, they aren't.
③How is the lion? ____ C. No, I don't.
④Are they tigers? ____ D. Yes, it is.
⑤Is this a kite?____ E. It is very strong.
