Which of the following statement is correct ?

Ileo-caecal valve guards the opening of ileum into caecum. It prevents the back flow of the faecal matter from the large intestine into the small intestine.Sphincter called the sphincter of Oddi guards the opening of the hepatopancreatic ampulla into the duodenum.The opening of the stomach into the duodenum is guarded by the pyloric sphincter.Gastro-oesophageal sphincter regulates the opening of oesophagus into the stomach.