This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gallbladder Cancer, Subject name: Surgery
[{'content': 'Commonest type of ca gallbladder with gall stones is: \nSelect and explain. \nA. Adenocarcinoma, B. Anaplastic carcinoma, C. Sq. cell carcinoma, D. Transitional cell ca', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' ie Adenocarcinoma almost 70% (90% according to Sabiston) of ca G.R. are associated with gall stones.Pathological types of G.B. carcinomaAdenocarcinoma90%Undifferentiated ca7%Squamous cell ca3%Now it's very easy to decide the commonest type of ca G.B. associated with Gall stones.", 'role': 'assistant'}]