－Lucy, you speak Chinese very well.

－Oh, really? __________.[ ]

A. Tank you

B. I'm sorry

C. That's OK

D. You're welcome

一张一元人民币能换（   ）张1角人民币；能换（   ）张伍角人民币。

一张十元人民币能换（   ）张五元人民币。