An engineer is adding a Cisco router to an existing environment. NTP authentication is configured on all devices in the environment with the command ntp authentication-key 1 md5 Clsc427128380. There are two routers on the network that are configured as NTP servers for redundancy, 192.168.1.110 and 192.168.1.111. 192.168.1.110 is configured as the authoritative time source. What command must be configured on the new router to use 192.168.1.110 as its primary time source without the new router attempting to offer time to existing devices?