In a standard Electrocardiogram (ECG), the 'QRS complex' represents: MCQ with Answer and Explanation

In a standard Electrocardiogram (ECG), the 'QRS complex' represents:
A. Atrial repolarization
B. Atrial depolarization
C. Ventricular depolarization
D. Ventricular repolarization
Answer: Option C
Solution (By JKSSB Mock Tests)
The QRS complex in an ECG represents the depolarization of the ventricles, which initiates ventricular contraction (systole). The P wave represents atrial depolarization. The T wave represents ventricular repolarization, which leads to ventricular relaxation (diastole). Atrial repolarization is usually masked by the larger QRS complex. Exam tip: P = atrial depolarization; QRS = ventricular depolarization; T = ventricular repolarization.

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