Given these four Class B networks: 172.104.0.0, 172.105.0.0, 172.106.0.0, 172.107.0.0, what is the supernet (CIDR) address that summarizes these four Class B networks? A. 172.104.0.0/12 B. 172.104.0.0/13 C. 172.104.0.0/14 D. 172.104.0.0/15