A：用导线将铁片和铜片连接后，放入一盛有稀 H2SO4溶液的烧杯中
B：Cu片作阳极，铁片作阴极，电解一定量的H2SO4溶液
C：Cu片作阴极，铁片作阳极，电解一定量的H2SO4溶液
D：将铁片直接放入一盛有稀 H2SO4溶液的烧杯中
It was such a long way that they didn't the hotel until it became dark.
下列是日常生活中采取的一些措施，正确的是（ ）
