Which of the following describes the term 'blank' in laboratory testing?

The term 'blank' in laboratory testing refers specifically to a sample that does not contain the analyte of interest. This sample is crucial for establishing a baseline measurement and helps to account for any background signals or noise that may occur in the testing process. By using a blank, laboratory professionals can ensure that the results obtained from the actual samples reflect only the presence of the analyte and not any interference from other sources.

By measuring the response of the blank, it is possible to identify and correct for any systematic errors that could affect the accuracy of the test results. This makes analysis more reliable, as it allows for a proper evaluation of the amount of analyte present in the test samples. In contrast, options regarding samples with known quantities of analyte or those used for calibration do not pertain to the definition of a 'blank,' and a sample tested for contaminants also serves a different purpose in the laboratory context.