Hydroxide Ion Concentration

A solution has a pH of 10.8 at 25° C. What is the hydroxide-ion concentration at 25° C?
A. 3.2 M
B. 4.1×10-2 M
C. 6.3×10-4 M
D. 1.6×10-11 M
E. 1.0×10-7 M