Answer:
T wave
Step-by-step explanation:
T wave are the wave which are is formed at end of fast phase of the ventricular repolarization. It is process by which ventricular myocytes return to the negative resting potential as they can be depolarized again.
This phase of cardiac cycle is rapid, so an low amplitude (upright) broad hump which follows QRS complex is seen in the T wave morphology.
Thus, T wave of ECG represents the ventricular repolarization and the relaxation of ventricular muscles which is known as ventricular diastole and thus precedes isovolumetric relaxation.