Final answer:
A T-tube is inserted to produce continuous postoperative drainage of the common bile duct, facilitating bile flow into the duodenum or an external pouch following surgery.
Step-by-step explanation:
The correct option for continuous postoperative drainage of the common bile duct is a T-tube. Its insertion is commonly done after procedures involving the biliary tract, such as the removal of gallstones or other surgeries that require bile duct access. Chest tubes are used for drainage of air, blood, or fluid from the pleural space in the chest. A Nasogastric tube (NG tube) is inserted through the nose into the stomach, primarily for feeding or medication administration, but can also be used to remove stomach contents. The Penrose drain is a soft flat tube used for draining fluids from surgical sites, but it is not specific to the bile duct. Thus, the T-tube is specially designed to facilitate the flow of bile into the duodenum or to an external pouch for bile drainage following surgery.