The 'P' wave in a standard ECG represents: MCQ with Answer and Explanation

The 'P' wave in a standard ECG represents:
A. Ventricular depolarization
B. Atrial repolarization
C. Ventricular repolarization
D. Atrial depolarization
Answer: Option D
Solution (By JKSSB Mock Tests)
An Electrocardiogram (ECG or EKG) is a graphical record of the heart's electrical activity. The 'P' wave represents the depolarization of the atria, which leads to atrial contraction. The QRS complex represents ventricular depolarization, and the 'T' wave represents ventricular repolarization, which leads to ventricular relaxation.

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