最具竞争性的招标采购方式是( )。
A．公开性招标采购
B．邀请性招标采购
C．限制性招标采购
D．选择性招标采购
参考答案：A
用所给词的正确形式填空。
1. There are many ____________ (shelf).
2. Our school is ____________ (big) than yours.
3. There are some ____________ (photo) of Peter on the wall.
4. I ______________(not see) my friend Judy for a long time.
5. Today is ____________ (me) first day of school this term.
PPP链路的状态为serial number is administratively down，line protocol is down时，说明（）。
A、物理链路有问题
B、接口被管理员shutdown了
C、参数配置不正确
D、没大问题，重启路由器就行了
