What does conductivity measure in an aqueous solution?

Conductivity measures the ability of an aqueous solution to carry electrical current. This property is primarily influenced by the presence and concentration of ions in the solution, such as those derived from salts, acids, or bases. When dissolved in water, these ions move freely and facilitate the flow of electricity. The higher the concentration of ions, the greater the conductivity, which is a crucial indicator of water quality, especially in water treatment processes.

Understanding conductivity is essential for monitoring the effectiveness of water treatment methods, as it provides insights into ion concentration and potential contaminants. While other choices like temperature and total dissolved solids relate indirectly to water quality, they do not specifically measure the conductive properties of the solution. Thus, recognizing that conductivity directly correlates with the solution's ability to carry electric current clarifies why this is the correct answer.