碘量法测定CuSO4含量，试样溶液中加入过量的KI，下列叙述其作用错误的是()

A、还原Cu2＋为Cu＋

B、防止I2挥发

C、与Cu＋形成CuI沉淀

D、把CuSO4还原成单质Cu

Having been told _____ where he lived, I had no difficulty in finding Peter's address. [ ]

A. exactly

B. approximately

C. appropriately

D. relatively