以下哪两个IP地址不在同一个网段
A.IP:10.20.30.40子网掩码:255.0.0.0和IP:10.20.50.60子网掩码:255.0.0.0
B.IP:10.20.30.40子网掩码:255.-255.0.0和IP:10.20.50.60子网掩码:255.255.0.0
C.IP:10.20.30.40子网掩码:255.255.255.0'和IP:10.20.50.60子网掩码:255.255.255.0
D.IP:192.168.20.30子网掩码:255.255.255.0和IP:192.168.20.50子网掩码:255.255.255.0
E.IP:172.16.20.30子网掩码:255.255.0.0和IP:172.16.10.20子网掩码:255.255.0.0