填空题

[说明]
某网络拓扑结构如图所示，在host1超级终端中查看路由器R1的路由信息如下所示。
Router # show ip route
C 192.168.100.0/24 is directly connected,FastEthernet0/0
R 192.168.101.0/24 [120/1] via 192.168.112.2,00:00:09,Serial2/0
192.168.112.0/30 is subnetted,1 subnets
C 192.168.112.0 is directly connected,Serial2/0
查看接口信息如下所示：
Router # show interface fastethernet0/0
FastEthernet0/0 is up,line protocol is up(connected)
Hardware is Lance,address is 000a.f35e.e172(bia 000a.f35e.e172)
Internet address is 192.168.100.1/24
MTU 1500 bytes,Bw 100000Kbit,DLY 100usec,rely 255/255,load 1/255
……


[问题1]
在设备连接方式中host1的______端口需和路由器R1的______端口相连；路由器R1采用______接口与交换机相连；路由器R1采用______接口与路由器R2相连。
空(1)～(4)备选答案：
A．Serial2/0 B．以太网 C．Corn(RS232) D．Console