This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Gallbladder, Subject name: Surgery
In a patient with gall stone disease, laproscopic cholecystectomy was performed & specimen was sent to pathology lab. The biopsied tissue was repoed as adenocarcinoma (Stage 1A ). What will be your treatment approach? 
Select and explain. 
A. Extended cholecystectomy, B. Chemotherapy, C. Observation & follow up, D. Extended cholecystectomy + Extended Right hepatectomy
C: Observation & follow up
Answer: C: Observation & follow up 
Explanation: Treatment is observation & follow up (as lap cholecystectomy is already performed) Staging & Treatment for CA Gall bladder IA - T1a Laproscopic cholecystectomy IB - T1b IIA - T2a IIB - T2b IIIA - T3 IIIB - T1-3 N1 Extended cholecystectomy IVA - T4 N0-1 Extended cholecystectomy+Extended R hepatectomy IVB - T any N any M2 Palliation(Chemotherapy)