This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
Only simple cholecystectomy is adequate in which stage of gallbladder cancer 
Select and explain. 
A. Stage IA, B. Stage IB, C. Stage III, D. Stage IV
A: Stage IA
Answer: A: Stage IA 
Explanation: Answer- A. Stage IAAccording to TNM staging, Simple cholecystectomy is done for T1a which is included in stage-I.T1a- simple cholecystectomyT1b, II & III- Extended cholecystectomyIV- Palliative treatment