In this case, the longest prefix of the candidate routes is 192.168.20.16/28, since its subnet mask (/28) is longer than the other entry's mask (/16), making the route more specific.
这种情况下，前缀最长的路由就是192.168.20.16/28，因为它的子网掩码（/28）比其他表项的掩码（/16）要长，使得它更加明确。