What portion of the ECG indicates ventricular repolarization?

Options

A. P wave.
B. QRS complex.
C. R spike.
D. T wave.

Answer

To determine which portion of the ECG indicates ventricular repolarization, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Components of an ECG**: An electrocardiogram (ECG) consists of several waves: the P wave, QRS complex, and T wave. Each of these components represents different electrical activities of the heart.

2. **Identify the P Wave**: The P wave represents atrial depolarization, which is the electrical activity associated with the contraction of the atria.

3. **Identify the QRS Complex**: The QRS complex represents ventricular depolarization, which is the electrical activity associated with the contraction of the ventricles.

4. **Identify the T Wave**: The T wave represents ventricular repolarization, which is the process of the ventricles recovering from depolarization and preparing for the next heartbeat.

5. **Conclusion**: Based on the identification of the components, the portion of the ECG that indicates ventricular repolarization is the T wave.

### Final Answer:
The T wave indicates ventricular repolarization.