What is the purpose of this command? ip route 0.0.0.0 0.0.0.0 serial0／0()

A. It configures a router to send all packets out interface serial 0/0.

B. It configures a router to block routing updates from being sent out interface serial 0/0.

C. It configures a router as a firewall, blocking all unauthorized packets from exiting serial 0/0.

D. It configures a router to send all packets for unknown destination networks out interface serial 0/0.

E. It configures a router to drop all packets for which the destination network is unknown.