A helpdesk operator is troubleshooting communications between devices in the same location, but one is having issues communicating with the others.

Which of the following will have issues?

Host D:IP: $192\mathrm{.}168\mathrm{.}0\mathrm{.}10,$ Mask: $255\mathrm{.}255\mathrm{.}255\mathrm{.}0$

Host B:IP: $192\mathrm{.}168\mathrm{.}1\mathrm{.}11,$ Mask: $255\mathrm{.}255\mathrm{.}255\mathrm{.}0$

Host C:IP: $192\mathrm{.}168\mathrm{.}1\mathrm{.}21,$ Mask: $255\mathrm{.}255\mathrm{.}0\mathrm{.}0$

Host A: IP: $192\mathrm{.}168\mathrm{.}1\mathrm{.}10,$ Mask: $255\mathrm{.}255\mathrm{.}255\mathrm{.}0$