题目

Some of the members demanded to know why they had been kept____the true facts until they reached the present critical stage.        A．in view of     B．in honor of      C．in place of         D．in ignorance of 答案：D一个年级有12个班，每个班有50名同学，随机编号为1～50，为了了解他们在课外的兴趣，要求每班第40号同学留下来进行问卷调查，这里运用的抽样方法是（　　）A．抽签法B．分层抽样法C．随机数表法D．系统抽样法