haihngm

However, this action is clearly counter to the governor’s ultimate goal, since after being released form prison, inmates who had taken such courses committed far fewer crimes overall than other inmates.
要证明的是这句话。你看两个样本比较，首先前提得正确无差异。C里面取非说，那些选择上课的人本身就是那种不太可能重新犯罪的人，这不是就说明了样本本身有差异性？所以错了。而C排除了这种可能。A跟这道题背道而驰啊！