What is a normal range for heart rate in a resting adult as seen in an ECG?

A normal resting heart rate for adults is typically between 60 and 100 beats per minute (bpm). This range is considered normal because it reflects the physiological requirements of the body at rest, ensuring that organs receive an adequate supply of blood and oxygen.

Values so low as 40-60 bpm might indicate bradycardia, which can be a concern depending on the individual's health status, particularly if accompanied by symptoms. On the other hand, rates above 100 bpm, such as those in the 100-120 bpm or 120-140 bpm ranges, can suggest tachycardia, which may also require medical attention depending on the context.

Therefore, the answer correctly identifies the normal resting heart rate range, which serves as a benchmark for assessing cardiovascular health in adults as observed on an ECG.