Which term describes the noninvasive test used to detect the heart's electrical activity?

• A. Electrocardiography
• B. Interval
• C. Bundle of His
• D. Precordial leads

Answer: (A)

The main idea is identifying the name of a noninvasive way to measure the heart’s electrical activity. That test is electrocardiography, commonly called an ECG or EKG. It works by attaching small electrodes to the skin (on the limbs and chest) to pick up the heart’s electrical signals. The machine then prints or displays an electrocardiogram, showing the timing and sequence of electrical events such as atrial depolarization (P wave), ventricular depolarization (QRS complex), and ventricular repolarization (T wave). This quick, painless test helps detect arrhythmias, conduction problems, and other heart issues. The other terms aren’t the test name: an interval is a duration between electrical events on the tracing; the Bundle of His is a component of the heart’s conduction system; precordial leads are the chest electrodes used during the recording, not the test itself.