正解:C
To allow an SSH connection to a router, the device must be configured to accept SSH connections on its VTY lines. This involves generating RSA keys with the command crypto key generate rsa, which is not shown in any of the options provided. However, option C shows the configuration of an access list that permits TCP traffic on port 22 (which is used by SSH) and applies it to a class map named "class-ssh". Then, a policy map named "CoPP" is configured with this class map and sets a police action for conforming traffic. While this does not show all steps required for enabling SSH, it is part of setting up Control Plane Policing (CoPP) which can protect against unwanted access including but not limited to SSH. References: Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) v1.1