Which of the following statements about fluorometry is true?

Fluorometry is a highly sensitive analytical technique that detects and quantifies compounds based on their natural fluorescence. Unsaturated cyclic molecules, such as certain aromatic compounds, often exhibit fluorescence due to the presence of conjugated double bonds that allow for electronic transitions when excited by a light source. The ability to absorb and re-emit light makes these molecules suitable candidates for detection in fluorometric analysis.

The sensitivity of fluorometry surpasses that of spectrophotometry, as fluorometry measures the emitted light after excitation, amplifying the signal and enabling the detection of lower concentrations of analytes. Additionally, fluorometry can be more specific in certain cases because it relies on the characteristic emission wavelengths of fluorescent compounds, distinguishing them from other components in a mixture.

Temperature typically affects fluorescence, but not in a simple proportional manner; it can change the intensity and decay of fluorescence due to variations in molecular motion and energy transfer processes, but it does not establish a direct proportional relationship. Therefore, the statement regarding unsaturated cyclic molecules being often fluorescent is the most appropriate description of the properties relevant to fluorometry.