A Solution with a PH of 9

A solution with a pH of 9.100 is prepared using aqueous ammonia and solid ammonium chloride.What is the ratio of [NH₃] to [NH₄⁺] in the solution? The K_b of ammonia is 1.76 * 10^-5.

A) 0.850 to 1
B) 1.02 to 1
C) 0.984 to 1
D) 1.41 to 1
E) 0.715 to 1