单项选择题
A. dig company.com ns
B. ipconfig/all
C. ifconfig-a
D. dig company.com mx
单项选择题 Which of the following commands is used to display other computers running on the network?（）
单项选择题 Which of the following wireless standards was the FIRST standard to be ratified and is used to support legacy wireless devices?（）
单项选择题 Which of the following is used to create multiple networks from one large network?（）