What happens to the pH of a solution when a strong base is added?

When a strong base is added to a solution, the pH increases, making the solution more basic. Strong bases, such as sodium hydroxide (NaOH), completely dissociate in water to produce hydroxide ions (OH⁻). The presence of these hydroxide ions raises the concentration of hydroxide in the solution, which in turn increases the pH value.

The pH scale ranges from 0 to 14, where a pH of 7 is considered neutral. Values above 7 indicate basicity, and values below 7 indicate acidity. When a strong base is introduced, it pushes the pH above 7, making the solution more alkaline. Therefore, option C correctly describes the effect on pH when a strong base is added to a solution.

In contrast, the other statements do not accurately reflect the behavior of pH in response to the addition of strong bases.