核磁共振现象的产生条件不包括Conditions for the generation of nuclear magnetic resonance phenomena are not included
A: 稳定的主磁场Stable magnetic field
B: 梯度磁场Gradient magnetic field
C: 磁矩不为零的自旋核Spin nuclei with non-zero magnetic moment
D: 具有一定能量的射频脉冲RF pulse with a certain energy