Which ducts join to form the common bile duct?

Which ducts join to form the common bile duct?

• A. Cystic and common hepatic
• B. Left hepatic duct and cystic duct
• C. Right hepatic duct and cystic duct
• D. Common hepatic duct and pancreatic duct

Answer: (A)

The common bile duct is formed where the cystic duct from the gallbladder joins the common hepatic duct, which itself is formed by the union of the right and left hepatic ducts. In other words, bile from the liver travels through the hepatic ducts to form the common hepatic duct, and when the cystic duct joins that duct, the result is the common bile duct. The other options don’t produce the common bile duct: merging with a pancreatic duct doesn’t form it (the pancreatic duct joins the common bile duct near the duodenum to drain at the major papilla), and pairing the cystic duct with a single hepatic duct from either side wouldn’t create the same vessel.

The common bile duct is formed where the cystic duct from the gallbladder joins the common hepatic duct, which itself is formed by the union of the right and left hepatic ducts. In other words, bile from the liver travels through the hepatic ducts to form the common hepatic duct, and when the cystic duct joins that duct, the result is the common bile duct. The other options don’t produce the common bile duct: merging with a pancreatic duct doesn’t form it (the pancreatic duct joins the common bile duct near the duodenum to drain at the major papilla), and pairing the cystic duct with a single hepatic duct from either side wouldn’t create the same vessel.