Final answer:
Intussusception is a major cause of bowel obstruction in children.
Step-by-step explanation:
The major cause of bowel obstruction in children is intussusception.
Intussusception is a condition in which one part of the intestine slides into an adjacent part, causing a blockage. It commonly occurs in infants and young children and is a medical emergency that requires immediate treatment. The exact cause of intussusception is unknown, but it is thought to be related to abnormal peristaltic movements in the intestine.