NEET 2023 Biology Solved Paper Code F1

Option (1) is the correct answer because the undigested food (faeces) enters into caecum of the large intestine through ileo-caecal valve, which prevents the backflow of the faecal matter.
Option (2) is not the answer because a muscular sphincter i.e., the gastro-oesophageal sphincter regulates the opening of oesophagus into the stomach.
Option (3) is not the answer because pyloric sphincter regulates the opening in between stomach and duodenum.
Option (4) is not the answer because the opening of common hepato-pancreatic duct is guarded by sphincter of Oddi.