Which of the following clinical manifestations differentiate myocardial infarction from angina pectoris?
A. chest pain affected by breathing and relieved by nitroglycerin administration
B. Chest pain initiated by exercise or stress and diaphoresis
C. Radiating chest pain, ST-segment changes on the ECG, and elevated serum levels of troponin
D. Chest pain aggravated by coughing and deep breathing