Proton nuclear magnetic resonance questions

${}^{\text{1}}$‍H and ${}^{\text{13}}$‍C are two of the most common nuclides studied by high-field NMR spectroscopy due to their abundance in human tissues. Other isotopes that have been studied include ${}^{\text{14}}$‍N, ${}^{\text{17}}$‍O, ${}^{\text{31}}$‍P, ${}^{\text{79}}$‍Br, and ${}^{\text{127}}$‍I. Based on this information, which of the following nuclides will NOT be considered suitable for use with NMR spectroscopy?