What are three problems with this design?

168.100.1 through 192.168.100.255

What are three problems with this design? (Choose three.)
A . The AREA 1 IP address space is inadequate for the number of users.
B . The AREA 3 IP address space is inadequate for the number of users.
C . AREA 2 could use a mask of /25 to conserve IP address space.
D . The network address space that is provided requires a single network-wide mask.
E . The router-to-router connection is wasting address space.
F . The broadcast domain in AREA 1 is too large for IP to function.

Answer: ACE

Explanation:

The given IP addresses of areas 1 and 3 along with network masks of 24 cannot accommodate

500 users so are inadequate, while the area 2 is having over capacity so its network mask can be reduced to 25 to accommodate the only 60 users it has.