当路由器启用NAT功能后，对局域网内部地址描述正确的是：（ ） Which of the following are correct about internal address of LAN after the router is enabled with NAT function?
选项：

A:局部地址是在内部网络中可见。 Local address is visible in internal network
B:局部地址是在内部网络中不可见。 Local address is invisible in internal network
C:全局地址则在外部网络上不可见。 Global address is invisible in external network
D:全局地址则在外部网络上可见 。Global address is visible in external network