甘草次酸的化学结构是（）
A.
B.
C.
D.
E.
参考答案：B
Lucy Lily may go to the concert with you. Because they are not allowed to go out on school
nights. [ ]
A. Either, or
B. Neither, nor
C. Both, and
D. Not only, but also
为了屏蔽不同计算机系统对键盘输入解释的差异，Telnet引入了()。
A．NVT
B．VPN
C．VLAN
D．VPI
