<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 25-year-old woman is brought to the emergency department by her roommate with severe right lower quadrant pain for the last 8 hours. The pain is progressively getting worse and is associated with vomiting. When you ask the patient about her last menstrual period, she tells you that although she stopped keeping track of her cycle after undergoing surgical sterilization 1 year ago, she recalls bleeding yesterday. The physical examination reveals a hemodynamically stable patient with a pulse of 90min, respiratory rate of 14min, blood pressure of 12570 mm Hg, and temperature of 37.0C 98.6F. The abdomen is tender to touch more tender in the lower quadrants, and tenderness at McBurneys point is absent. Which of the following is the best next step in the management of this patient?? A: Urinary human chorionic gonadotropin hCG, B: Urinalysis, C: FAST ultrasound scan, D: Complete blood count, E: Appendectomy,  <response>: This is a clinical vignette describing a 25-year-old woman with severe right lower quadrant abdominal pain, vomiting, and vaginal bleeding the day before, concerning for ectopic pregnancy. The key findings are right lower quadrant pain, vomiting, and vaginal bleeding in a reproductive age woman. An ectopic pregnancy should be ruled out first before considering other causes of abdominal pain. A urine hCG test is the best initial test to diagnose ectopic pregnancy. A FAST ultrasound can also visualize an ectopic pregnancy but an hCG test is more sensitive. The other tests - urinalysis, CBC, and appendectomy are not appropriate next steps.A: Urinary human chorionic gonadotropin hCG 