Alex Goes to the Hospital for a Checkup After Experiencing

Alex goes to the hospital for a checkup after experiencing severe chest pain.After a preliminary physical examination,a health care professional asks Alex to lie down,places small metal disc electrodes on his body,and hooks the electrodes up to a machine that starts recording the electrical activity of Alex's heart.After the procedure,the health care professional hands over the recording to a doctor for analysis.This recording is known as a(n) _____.

A) encephalogram
B) mammogram
C) electrocardiogram
D) angiogram