At equivalence point $\mathbf { X ~ m l }$ of $\mathbf { 0 . 0 2 ~ M ~ H C l }$ has reacted with $\mathbf { 5 ~ m L }$ of $\mathbf { 0 . 0 2 ~ M }$ of a weak base. The $\mathbf { p K } _ { \mathbf { b } }$ of weak base is $\mathbf { 5 . 6 9 }$ and the pH of the resulting solution is Y at half of the equivalence point. The value of $( \mathrm { x } + \mathrm { y } )$ is:
(A) 8.81
(B) 5
(C) 3.81
(D) 13.31