Q. A 28-year-old woman presents at the emergency department with symptoms of palpitations, severe sweating, and shaking. Her blood pressure is alarmingly high, measuring at 185/110 mmHg. Laboratory results reveal an increase in catecholamine levels. Further investigation leads to a diagnosis of pheochromocytoma, a tumor of the adrenal medulla causing an overproduction of catecholamines. A medical student involved in the case recalls that norepinephrine can be converted into epinephrine in the adrenal medulla, contributing to the patient's condition. What enzyme is responsible for this conversion?