Answer:
The correct answer will be option-A
Explanation:
Electrocardiogram or ECG is the recording and representation of the electrical changes that are taking place during the cardiac cycle.
The QRS complex is preceded by the P wave or atrial systole or atrial depolarization after which the electrical signals are passed on to the AV node.
As soon as the AV node passes the electrical signals to bundle of His, it is observed in as the QRS interval which represents the atrial diastole and the onset of ventricular depolarization.
Thus, option-true is the correct answer.