Which of the following options ranks the groups in order of decreasing priority according to the Cahn-Ingold-Prelog system, starting with the highest priority group first? Select the single best answer.
$ONH_2 > NHCH_3 > CH_2NHCH_3$
$ONH_2 > NHCH_3 > CH_2NH_2$
$ONHCH_3 > NH_2 > CH_2NH_2$
$ONH_2 > NHCH_3 > CH_2NH_2$
$ONHCH_3 > NH_2 > CH_2NHCH_3$