A$-1.$ What is the network address assigned to your ISP?$$

Question $1$ options:

$99\mathrm{.}5\mathrm{.}0\mathrm{.}0/18$

$99\mathrm{.}5\mathrm{.}128\mathrm{.}0/18$

$99\mathrm{.}5\mathrm{.}192\mathrm{.}0/18$

$99\mathrm{.}5\mathrm{.}255\mathrm{.}0/18$

None of the given options