Router1：

 [Router1]interface Serial 0/2/0

 [Router1-Serial0/2/0]ip address 10.1.1.1 24

 [Router1]interface loopback 0 

[Router1-LoopBack0]ip address 1.1.1.1 32 

[Routerl]interface Tunnel 0 

[Router1-Tunnel0]source 10.1.1.1 

[Router1-Tunnel0]destination 20.1.1.2

 [Router1-Tunnel0]ip address 100.1.1.1 24 

[Router1]ospf 

[Router1-ospf-1]area 0 

[Router1-ospf-1-area-0.0.0.0] network 10.1 .1 .1 0.0.0.255

 [Router1]ip route-static 3.3.3.3 32 100.1.1.2

 Router2:

 [Router2]interface Serial 0/2/0

 [Router2-Serial0/2/0]ip address 10.1.1.2 24 

[Router2]interface Serial 0/2/1 

[Router2-Serial0/2/1]ip address 20.1.1.1 24

 [Router2]ospf 

[Router2-ospf-1]area 0

 [Router2-ospf-1-area-0.0.0.0] network 10.1.1.2 0.0.0.255 

[Router2-ospf-1-area-0.0.0.0] network 20.1.1.1 0.0.0.255

Router3: 

[Router3]interface Serial 0/2/0 

[Router3-Serial0/2/0]ip address 20.1.1.2 24

 [Router3]interface loopback 0 

[Router3-Loop Back0]ip address 3.3.3.3 32 

[Router3]interface Tunnel 0

 [Router3-Tunnel0]source 20.1.1.2 

[Router3-Tunnel0]destination 10.1.1.1

 [Router3-Tunnel0]ip address 100.1.1.2

 [Router3]ospf 

[Router3-ospf-l]area 0

 [Router3-ospf-l-area-0.0.0.0] network 20.1.1.2 0.0.0.255

 [Router3]ip route-static 1.1.1.1 32 100.1.1.1

在Router上使用命令 ping -a 1.1.1.1 3.3.3.3，检查连通性， l00%收到 icmp回包。上进过程中，以下对各路由器对数据包的处理过程酌描述，正确的是 _____。