When 10 mL of 0.01 M HCl was added to a mixture of 0.5 M $$\text{NH}_3$$ and 0.5 M $$\text{NH}_4\text{Cl}$$, the pH of the resultant solution will be, given that the $$pK_b$$ of $$\text{NH}_3$$ is 4.75

A

9.07

B

9.75

C

9.25

D

8.75