$38.$ A $300\mathrm{.}0mL$ portion of $H_{2}O$ is added to $300\mathrm{.}0mL$ of $0\mathrm{.}250M{H}_{2}S{O}_4.$ What is the new molarity?

$($A$)0\mathrm{.}125M$

$($B$)0\mathrm{.}250M$

$($C$)0\mathrm{.}500M$

$($D$)0\mathrm{.}250M$