Refer to the exhibit. 
The enterprise has decided to use the network address 172.16.0.0. The network administrator
needs to design a classful addressing scheme to accommodate the three subnets, with 30, 40,
and 50 hosts, as shown. What subnet mask would accommodate this network?
A.
255.255.255.192
B.
255.255.255.224
C.
255.255.255.240
D.
255.255.255.248
E.
255.255.255.252
Explanation: