This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Anatomy
All of the following are the risk factors for carcinoma Gallbladder except 
Select and explain. 
A. Primary sclerosing cholangitis, B. Procelain gallbladder, C. Multiple 2cm gallstones, D. Choledochal cyst
C: Multiple 2cm gallstones
Answer: C: Multiple 2cm gallstones 
Explanation: Risk factors for Carcinoma Gallbladder Gallstones >3cm Procelain gallbladder Anomalous pancreaticobiliary junction (APBDJ) Choledochal cysts Adenomatous polyps Primary sclerosing cholangitis Obesity Salmonella typhi infection Ref: Sabiston 20th edition Pgno :1510