磁共振质子群能态跃迁，是指：（ ）The energy state transition of proton group in magnetic resonance is defined as （ ）
A、低能态跃迁到中等能态Transition from low energy state to medium energy state
B、中等能态跃迁到高能态Transition from medium energy state to high energy state
C、高能态跃迁到低能态Transition from high energy state to low energy state
D、低能态跃迁到高能态Transition from low energy state to high energy state