单项选择题
A.ermit all packets matching the first three octets of the source address to all destinations
B.permit all packet matching the last octet of the destination address and accept all source addresses
C.permit all packet matching the host bits in the source address to all destinations
D.permit all packet from the third subnet of the network address to all destinations
单项选择题 GivenanIPaddress172.16.28.252withasubnetmaskof255.255.240.0，whatisthecorrectnetworkaddres？（）
单项选择题 What is the name of the VTP mode of operation that enables a switch to forward only VTPadvertisements while still permitting the editing of local VLAN information?（）
单项选择题 Which command can be arouter to verify the layer 3 path to a host?（）