Final answer:
MI refers to the injury or necrosis of the heart muscle due to a heart attack option (C). It is caused by the blockage of a coronary artery, which can lead to chest pain, pressure, and possibly other symptoms or asymptomatic presentations.
Step-by-step explanation:
Myocardial Infarction (MI), which is commonly known as a heart attack, refers to C. Injury or necrosis of the heart muscle resulting from a heart attack. An MI usually occurs because of a complete blockage of a coronary artery, which can be due to a blood clot or the rupture of atherosclerotic plaque. This leads to the death of myocardial cells as they are deprived of oxygen and nutrients. Key symptoms of an MI include chest pain, pressure, and potentially other ailments, though some MIs can be asymptomatic. If untreated, an MI can result in serious complications such as heart arrhythmias, heart failure, and even sudden death.