汇票中的付款人是否具有必须付款的义务，主要基于其是否作出______行为。
A．出票 B．背书C．承兑 D．保证
参考答案：C
You________all those clothes！We have a washing machine to do that sort of thing.[ ]
A. needn’t have washed
B. shouldn’t have washed
C. must not have washed
D. can not have washed
轻制墙板有那些品种？它们公共的特点是什么？
