Final answer:
The correct subnet mask from the options listed is 255.255.0.0, which is a standard Class B network subnet mask.
Step-by-step explanation:
The valid subnet mask out of the options provided is 255.255.0.0. This is a standard subnet mask for a Class B network, which supports up to 65,536 hosts on the network. Subnet masks are used in IP networking to separate the host address from the network address. The other options provided are not valid subnet masks: 192.168.1.1 is a typical private IP address, 0.0.0.0 represents a default route in networking, and 'None of these' is not applicable in this particular case.