question: Q:A 39-year-old woman comes to the physician because of a 5-month history of episodic retrosternal chest pain. She currently feels well. The pain is unrelated to exercise and does not radiate. The episodes typically last less than 15 minutes and lead to feelings of anxiety; resting relieves the pain. She has not had dyspnea or cough. She has hyperlipidemia treated with simvastatin. She does not smoke, drink alcohol, or use illicit drugs. Her temperature is 37°C (98.6°F), pulse is 104/min, respirations are 17/min, and blood pressure is 124/76 mm Hg. Cardiopulmonary examination shows no abnormalities. An ECG shows sinus tachycardia. Which of the following is the most appropriate next step in the evaluation of coronary artery disease in this patient?? 
  {'A': 'Coronary CT angiogram', 'B': 'Nuclear exercise stress test', 'C': 'Troponin I measurement', 'D': 'No further testing needed', 'E': 'Dobutamine stress echocardiography'},