How is electrocardiography best defined?

Electrocardiography is best defined as a process of recording the electrical activity of the heart. This definition captures the essential purpose of an electrocardiogram (EKG or ECG), which is to assess how the heart's electrical impulses trigger heartbeats. By measuring these electrical signals, healthcare professionals can evaluate the heart's rhythm, identify abnormalities, diagnose various cardiac conditions, and monitor the heart's overall health.

In the context of the other choices, while measuring blood flow, visualizing heart valves, and recording heart sounds are all important aspects of cardiovascular assessment, they do not specifically pertain to the definition of electrocardiography. The primary focus of this technique lies in the electrical aspects of cardiac function, making it distinct from the tasks of blood flow measurement or heart sound analysis.