A customer requested a GRE tunnel through the provider network between two customer sites using loopback to hide internal networks. Which configuration on R2 establishes the tunnel with R1?
A. R2(config)# interface Tunnel 1
R2(config-if)# ip address 172.20.1.2 255.255.255.0
R2(config-if)# ip mtu 1400
R2(config-if)# ip tcp adjust-mss 1360
R2(config-if)# tunnel source 192.168.20.1
R2(config-if)# tunnel destination 192.168.10.1
B. R2(config)# interface Tunnel 1
R2(config-if)# ip address 172.20.1.2 255.255.255.0
R2(config-if)# ip mtu 1400
R2(config-if)# ip tcp adjust-mss 1360
R2(config-if)# tunnel source 10.10.2.2
R2(config-if)# tunnel destination 10.10.1.1
C. R2(config)# interface Tunnel 1
R2(config-if)# ip address 172.20.1.2 255.255.255.0
R2(config-if)# ip mtu 1500
R2(config-if)# ip tcp adjust-mss 1360
R2(config-if)# tunnel source 192.168.20.1
R2(config-if)# tunnel destination 10.10.1.1
D. R2(config)# interface Tunnel 1
R2(config-if)# ip address 172.20.1.2 255.255.255.0
R2(config-if)# ip mtu 1500
R2(config-if)# ip tcp adjust-mss 1360
R2(config-if)# tunnel source 10.10.2.2
R2(config-if)# tunnel destination 10.10.1.1
