单项选择题 An administrator replaced a router with a switch. End users are able to access network shares butare not able to access the Internet. Which of the following is the BEST explanation why the usersare unable to access the Internet?（）

单项选择题 Which of the following logical network topologies is used to provide a secure connection acrossthe Internet?（）

单项选择题 Which of the following technologies facilitates the conversion of internal private IP addressing toexternal public IP addressing?（）