select the correct asnswe. we are told yhat the network we are dealing with is a standard class B net work ie$.$ there is NO subnetting involved here. what would be the subnet mask asociaate with this network

A $255\mathrm{.}255\mathrm{.}255\mathrm{.}0$

B$.255\mathrm{.}255\mathrm{.}255\mathrm{.}240$

C$.255\mathrm{.}255\mathrm{.}0\mathrm{.}0$

D$.$ none of the above