This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Stomach and Intestines, Subject name: Pediatrics
[{'content': 'Commonest cause of intestinal obstruction in children is: \nSelect and explain. \nA. Intussusception, B. Volvulus, C. Hernia, D. Adhesions', 'role': 'user'}, {'content': "Answer: A \nExplanation: a. Intussusception(Ref: Nelson's 20/e p 1894-1897', Ghai 8/e p 285-286)Intussusception occurs when a portion of the alimentary tract is telescoped into an adjacent segment.", 'role': 'assistant'}]