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': 'The first to appear in a cause of acute intestinal obstruction is - \nSelect and explain. \nA. Constipation, B. Colicky pain, C. Vomiting, D. Distension', 'role': 'user'}, {'content': 'Answer: B \nExplanation: • Symptoms of intestinal obstruction: Pain, vomiting, distention and constipation\n• Pain is the first symptom encountered; it occurs suddenly and is usually severe.\nPain in Intestinal Obstruction\n• It is colicky in nature and is usually centred on the umbilicus (small bowel) or lower abdomen (large bowel)\n• The pain coincides with increased peristaltic activity\n• With increasing distension, the colicky pain is replaced by a mild constant diffuse pain\n• The development of severe pain is indicative of the presence of strangulation\n• Pain may not be a significant feature in postoperative simple mechanical obstruction and does not usually occur in paralytic ileus', 'role': 'assistant'}]