单项选择题
When is it necessary to use a public IP address on a routing interface?（）
A. Connect a router on a local network. B. Connect a router to another router. C. Allow distribution of routes between networks. D. Translate a private IP address. E. Connect a network to the Internet.
单项选择题 What will happen if a private IP address is assigned to a public interface connected to an ISP?（）
单项选择题 Which IP address can be assigned to an Internet interface?（）
单项选择题 What is the principle reason to use a private IP address on an internal network?（）
