What Is the Hydronium Ion Concentration of a 0 $\times$ 10^-5 $\times$

What is the hydronium ion concentration of a 0.010 M acetic acid solution? (K_a for acetic acid is 1.76 $\times$ 10^-5.)

A) 1.8 $\times$ 10^-3
B) 1.8 $\times$ 10^-5
C) 1.0 $\times$ 10^-2
D) 1.8 $\times$ 10^-7
E) 4.2 $\times$ 10^-4