The administrator should use 172.16.19.241 as an IP address to be in compliance with RFC 1918 standard.
RFC 1918 defines three ranges of IP addresses that are reserved for private internets, meaning they are not globally routable on the public Internet and can be used within an enterprise without any risk of conflict or overlap with other networks. These ranges are:
10.0.0.0 - 10.255.255.255 (10/8 prefix) 172.16.0.0 - 172.31.255.255 (172.16/12 prefix) 192.168.0.0 -
192.168.255.255 (192.168/16 prefix)
Out of these ranges, only 172.16.19.241 falls within one of them (172.16/12 prefix). The other options are either public IP addresses that belong to other organizations or networks (11.251.196.241, 171.245.198.241) or invalid IP addresses that do not conform to any standard (193.168.145.241).
Reference: https://whatis.techtarget.com/definition/RFC-1918