[Expert Solution]: A 74-year-old man presents to the…

A 74-year-old man presents to the emergency department with severe lightheadedness and presyncope that started after he had a bowel movement with a significant amount of blood in it. He has not had any vomiting. His chronic medical problems are hypertension and type 2 diabetes. He has no prior history of GI bleeding and had a normal screening colonoscopy 5 years ago. His medications are metformin, low-dose aspirin, and lisinopril. His blood pressure is 78/50 mm Hg, pulse is 140/min with a regular rhythm, respirations are 18/min, and oxygen saturation is 94%. After an initial successful resuscitation with intravenous fluids, what is the next most appropriate step in managing this patient? A. Colonoscopy B. Nasogastric lavageO C. Upper GI endoscopy D. Angiography E. Radionuclide imaging