Which statement best describes qualitative testing?

The statement that best describes qualitative testing is that it focuses on whether a substance is present. Qualitative tests are designed specifically to determine the presence or absence of a particular substance, such as a pathogen, drug, or analyte, without providing a quantitative measurement of how much of that substance is present. For example, a qualitative test might indicate whether a urine sample contains glucose or if a blood sample tests positive for a specific infection, but it does not quantify the levels of glucose or the severity of the infection.

In contrast, options suggesting that qualitative testing provides definite numerical data or measures only physical properties do not accurately represent the nature of qualitative assessments. Additionally, the assertion that qualitative testing is not used in clinical settings is misleading, as such tests play a crucial role in many diagnostic processes within clinical environments.