The HEIGHT of a peak on an MR spectrum correlates to the _________ of a substance that was detected.

The height of a peak on an MR spectrum directly correlates to the amount of a substance that was detected. In magnetic resonance spectroscopy, the peaks represent different chemical species, and the intensity or height of each peak indicates the concentration of those species within the sample being analyzed. A taller peak signifies a higher concentration, while a shorter peak indicates a lower concentration. This quantification is crucial in various applications, such as metabolomics or evaluating tissue composition.

Understanding this relationship helps in interpreting MR spectra accurately, allowing practitioners to draw relevant conclusions about the biochemical environment or pathological conditions. The other options relate to different concepts in MRI, such as frequency, T1, and T2 relaxation times, which are important for image contrast but do not relate to the quantification of substances indicated by peak height in the spectrum.