<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 31-year old man presents to the emergency department for blood in his stool. The patient states that he saw a small amount of bright red blood on his stool and on the toilet paper this morning, which prompted his presentation to the emergency department. The patient denies any changes in his bowel habits or in his weight. The patient has a past medical history of asthma managed with albuterol and fluticasone. The patient has a family history of alcoholism in his father and suicide in his mother. His temperature is 97F 36.1C, blood pressure is 12077 mmHg, pulse is 60min, respirations are 12min, and oxygen saturation is 98 on room air. On physical exam, the patient has a cardiac and pulmonary exam that are within normal limits. On abdominal exam, there is no tenderness or guarding and normal bowel sounds. Laboratory values are ordered and return as below.Hemoglobin: 15 gdLHematocrit: 42Leukocyte count: 4,500 cellsmm3 with normal differentialPlatelet count: 230,000mm3Serum:Na: 139 mEqLCl-: 100 mEqLK: 4.3 mEqLHCO3-: 24 mEqLBUN: 20 mgdLGlucose: 92 mgdLCreatinine: 1.0 mgdLCa2: 9.9 mgdLWhich of the following is the next best step in management?? A: Anoscopy, B: Colonoscopy, C: CT scan, D: Mesalamine enema, E: Stool culture and analysis for red blood cells and leukocytes,  <response>: This is a patient presenting with bright red blood per rectum, which indicates lower gastrointestinal bleeding. The key findings in the stem are the bright red blood on stool and toilet paper, no changes in bowel habits or weight, normal vital signs, and unremarkable physical exam except for the lower GI bleeding. The normal hemoglobin, hematocrit, and hemodynamic stability indicate this is likely a minor bleed. The next step is to determine the source of bleeding, whether it is coming from the colon, anorectal region, or hemorrhoids. Choice A anoscopy allows direct visualization of the anorectal region to check for hemorrhoids or anal fissures. Choice B colonoscopy examines the entire colon but is more invasive. Choice C CT scan may miss small lesions and has radiation exposure. Choice D mesalamine enema treats inflammatory bowel disease but the cause of bleeding is unknown. Choice E stool studies may show presence of blood but does not localize source.A: Anoscopy 