What is the function of an indicator in a solution?

An indicator serves the important function of differentiating between acid and base solutions by changing color in response to changes in pH. This color change allows one to visually assess the acidity or basicity of a solution. For example, litmus paper, a common indicator, turns red in acidic solutions and blue in basic solutions. This property is essential in various chemical tests and applications, including those in funeral service education where pH levels might be relevant in embalming fluid formulation or other chemical processes.

In the context of the other options, while indicators may dissolve in the solution, this is not their primary function. Similarly, indicators do not change pH levels themselves; they simply signal the existing pH. Neutralizing acids is a different chemical action that does not pertain to the role of an indicator. Thus, the correct choice clearly highlights the primary role of indicators in chemical analysis.