The old woman became aware of         when she left the market.    [ ]

A．cheating        

B．cheated    

C．being cheated    

D．to be cheated

绝对剩余价值生产的前提条件是

A．剩余劳动时间不变
B．必要劳动时间不变
C．工作日长度不变
D．无偿劳动时间不变