Which term is the device that records the heart's activity on heat-sensitive graph paper?

Which term is the device that records the heart's activity on heat-sensitive graph paper?

• A. Standard limb lead
• B. ST segment
• C. Stylus
• D. Treadmill test

Answer: (C)

The key idea is identifying what physically writes the heart’s electrical activity onto the ECG paper. In an ECG machine, the electrical signals from the heart are amplified and then traced onto heat‑sensitive graph paper by a recording device called the stylus. As the machine processes the signal, the stylus moves to produce the characteristic waveforms on the paper. The other terms refer to parts of the ECG system or features of the tracing (a limb lead is an electrode configuration, the ST segment is a portion of the waveform, and a treadmill test is a stress test). So the device that records on the heat‑sensitive paper is the stylus.

The key idea is identifying what physically writes the heart’s electrical activity onto the ECG paper. In an ECG machine, the electrical signals from the heart are amplified and then traced onto heat‑sensitive graph paper by a recording device called the stylus. As the machine processes the signal, the stylus moves to produce the characteristic waveforms on the paper. The other terms refer to parts of the ECG system or features of the tracing (a limb lead is an electrode configuration, the ST segment is a portion of the waveform, and a treadmill test is a stress test). So the device that records on the heat‑sensitive paper is the stylus.