The sphincter of Oddi found in man, guards the
a)	Pancreatic duct	b)	Hepatopancreatic duct
c)	Bile duct	d)	Cystic duct

(b)

In liver, right and left hepatic ducts join to form a common hepatic duct which joins the duct of gall bladder (cystic duct), forming a common bile duct or ductus choledocus.  The later opens into the proximal part of duodenum through a valvular pore guarded by sphincter called sphincter of Oddi.