A.
R1 -
interface Tunnel1
ip address 1.1.1.13 255.255.255.0
tunnel source Loopback0
tunnel destination x.y.z.110
R3 -
interface Tunnel
ip address 1.1.1.31 255.255.255.0
tunnel source Loopback0
tunnel destination x.y.z.160
B.
R1 -
interface Tunnel1
ip address 1.1.1.13 255.255.255.0
tunnel source Loopback0
tunnel destination x.y.z.160
R3 -
interface Tunnel1
ip address 1.1.1.31 255.255.255.0
tunnel source Loopback0
tunnel destination x.y.z.110
C.
R1 -
interface Tunnel2
ip address 1.1.1.12 255.255.255.0
tunnel source Loopback0
tunnel destination x.y.z.125
R2 -
interface Tunnel1
ip address 1.1.1.125 255.255.255.0
tunnel source Loopback0
tunnel destination x.y.z.110
interface Tunnel3
ip address 1.1.1.125 255.255.255.0
tunnel source Loopback0
tunnel destination x.y.z.160
R3 -
interface Tunnel2
ip address 1.1.1.32 255.255.255.0
tunnel source Loopback0
tunnel destination x.y.z.125
D.
R1 -
interface Tunnel1
ip address 1.1.1.13 255.255.255.0
tunnel source Loopback0
tunnel destination x-y.z.110
R3 -
interface Tunnel1
ip address 1.1.1.31 255.255.255.0
tunnel source Loopback0
tunnel destination x.y.z.125