Calculate the pH at $25\%$ titration in the titration of both protons of the diprotic acid H$2$A with $0\mathrm{.}100$ MNaOH, starting with $100$ml$,2$of $0\mathrm{.}100$ MH$2$A$.$ Kal$=1\mathrm{.}0$ x $10,$ Ka$2=1\mathrm{.}0$x $10$ A$.7\mathrm{.}6$ B$.24$ C$\mathrm{.}8$ D$.12$