In the following figure, what needs to be changed for Computer A to successfully communicate with Computer B (assume the least amount of effort to fix the problem)?

The default gateway address for Computer A is 192.168.1.63. The IP address on the router (default gateway) is the broadcast address for the 192.168.1.0/26 network and cannot be used as that network's gateway. If you were to change Computer A's IP address, it would still not be able to communicate with Computer B because of the incorrect gateway address. Computer B's IP address and default gateway are fine, and both will function properly.