This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
[{'content': 'A patient is admitted to the hospital with complaints of nausea, vomiting, diarrhoea, and severe abdominal pain. Which of the following would immediately alert the nurse that the patient has bleeding from the GI tract? \nSelect and explain. \nA. Complete blood count., B. Guaiac test., C. Vital signs., D. Abdominal girth.', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Option B:\xa0To assess for GI tract\xa0bleeding\xa0when frank blood is absent, the nurse has two options: She can test for occult blood in vomitus, if present, or in stool – through guaiac (Hemoccult) test.\nOption A:\xa0A complete blood count does not provide immediate results and does not always immediately reflect blood loss.\nOption C:\xa0Changes in vital signs may be caused by factors other than blood loss.\nOption D:\xa0Abdominal girth is unrelated to blood loss.', 'role': 'assistant'}]