Calculate the concentration of OH^- ions in a solution where the concentration of H⁺ ions is 1.0 x 10^-4 M at 25 degrees Celsius.

• A. 1.0 x 10^-4 M
• B. 1.0 x 10^-7 M
• C. 1.0 x 10^-10 M
• D. 1.0 x 10^-14 M

Answer: (C)