单项选择题
A. Show history
B. Show buffers
C. Show typed commands
D. Show terminal buffer
E. Show command
单项选择题 After logging into a router and typing in a few show commands, you press the up arrow key. What will this do?（）
单项选择题 You just purchased a refurbished router that contains a configuration from a previous deployment. What should you do, before entering a new configuration into the router?（）
单项选择题 In the Cisco IOS, what is the definition of a global command?（）