A teacher should have the ability to be ____ his or her class.

A．in the charge of

B．in memory of

C．in control of

D．in favor of

根据网络拓扑和要求，解释并完成路由器R1上的部分配置。
R1 fconfig)#crypto isakmp enable (启用IKE)
R1 (config)#crypto isakmp (1) 20 (配置IKE策略20)
R1 (config-isakmp)# authentication pre-share (2)
R1 (config-isakmp)#exit
R1 fconfig)#crypto isakmp key 378 address 192.168.2.2(配置预共享密钥为378)
R1 (config)#access-list 101 permit ip (3) 0.0.0.255 (4) 0.0.0.255 (设置ACL)