What Is the Concentration of OH^- in a 0

What is the concentration of OH^- in a 0.083 M NaOH solution?

A) 0.083 M
B) 1.21 × 10^{-13 M}
C) 8.30 × 10^{-16 M}
D) 7 M
E) 8.30 × 10^{12 M}