For the following options， which feature is the foundation of Cisco Self-Defending Network technology？（）

A.It validates the fact that a packet is either a connection request or a data packet belonging to a connection
B.It evaluates network packets for valid data at the application layer before allowing connections
C.It analyzes network traffic at the network and transport protocol layers
D.It keeps track of the actual communication process through the use of a state table

A.displays a screen with Fix-it check boxes to let you choose which potential security-related configuration changes to implement
B.has two modes of operationinteractive and non-interactive
C.automatically enables Cisco IOS firewall and Cisco IOS IPS to secure the router
D.uses interactive dialogs and prompts to implement role-based CLI
E.requires users to first identify which router interfaces connect to the inside network and which connectto the outside network

A.When the router goes into quiet mode， any host is permitted to access the router via Telnet，SSH， and HTTP，since the quiet-mode access list has not been configured.
B.The login block-for command is configured to block login hosts for 93 seconds.
C.All logins from any sources are blocked for another 193 seconds.
D.Three or more login requests have failed within the last 100 seconds.