单项选择题
A．there are few others like it B．there are no errors on the stamps C．a mistake is made in the ,printing D．both A and C
A．60 years. B．31 years. C．50 years. D．21 years.
A．unwelcome by the AF of L B．not reached until after the Knights of Labor died out C．not helpful to women D．welcome by factory owner