The correct option is C Both A and B
Myocardial infarction (MI) occurs, when blood flow stops to part of the heart causing damage to the heart muscle. Atherosclerosis is a disease in which plaque builds up inside the arteries. Smoking is known to be a strong risk factor for premature atherosclerosis, myocardial infarction and sudden cardiac death. Smoking appears to be the cause of about 36% of deaths due to MI.
Thus, the correct answer is option (C), 'Both A and B'.