A 45-year-old obese Native American female presents to the ER complaining of severe cramping right upper abdominal pain, nausea, vomiting, and a mild fever. Her AST and ALT are normal, while GGT, alk...

A 45-year-old obese Native American female presents to the ER complaining of severe cramping right upper abdominal pain, nausea, vomiting, and a mild fever. Her AST and ALT are normal, while GGT, alk phos, and conjugated bilirubin are all markedly elevated. Her CBC also reveals leukocytosis. On physical exam, an enlarged tense gallbladder is palpable. What is the most likely etiology?

A. Cholelithiasis

B. Cholangiocarcinoma

C. Choledocholithiasis

D. Cholecystitis