单项选择题
Which option is a valid IPv6 address?（）
A. 2001:0000:130F::099a::12a B. 2002:7654:A1AD:61:81AF:CCC1 C. FEC0:ABCD:WXYZ:0067::2A4 D. 2004:1:25A4:886F::1
单项选择题 What is known as "one-to-nearest" addressing in IPv6?（）
单项选择题 Which type of cable is used to connect the COM port of a host to the COM port of a router or switch?（）
单项选择题 Which Cisco Catalyst feature automatically disables the port in an operational PortFast upon receipt of a BPDU?（）
