Q4. Which of the following components of an ECG represents ventricular depolarisation?a) P waveb) T wavec) QRS complexd) P-Q interva

The component of an ECG that represents ventricular depolarization is the QRS complex. So, the answer is c) QRS complex.

Here's a step-by-step explanation:

1. An ECG, or electrocardiogram, is a test that measures the electrical activity of the heartbeat.

2. Each beat of the heart is represented on the ECG as a series of waves: the P wave, the QRS complex, and the T wave.

3. The P wave represents the depolarization of the atria, or the upper chambers of the heart.

4. The QRS complex, which is a combination of three of the graphical deflections seen on a typical ECG, represents the depolarization of the ventricles, or the lower chambers of the heart.

5. The T wave represents the repolarization of the ventricles.

6. The P-Q interval, or PR interval, represents the time that electrical impulses take to travel from the sinus node through the AV node, where they are slowed down to allow the ventricles to fill with blood.

So, the QRS complex is the part of the ECG that represents ventricular depolarization.